An issue was discovered in the Linux kernel before 6.6.8. rose_ioctl in net/rose/af_rose.c has a use-after-free because of a rose_accept race condition.

It was found that cifs-utils' mount.cifs was invoking a shell when requesting the Samba password, which could be used to inject arbitrary commands. An attacker able to invoke mount.cifs with special permission, such as via sudo rules, could use this flaw to escalate their privileges.

In RDoc 3.11 through 6.x before 6.3.1, as distributed with Ruby through 3.0.1, it is possible to execute arbitrary code via | and tags in a filename.

A vulnerability in the shared library loading mechanism of Cisco AnyConnect Secure Mobility Client for Linux and Mac OS could allow an authenticated, local attacker to perform a shared library hijacking attack on an affected device if the VPN Posture (HostScan) Module is installed on the AnyConnect client. This vulnerability is due to a race condition in the signature verification process for shared library files that are loaded on an affected device. An attacker could exploit this vulnerability by sending a series of crafted interprocess communication (IPC) messages to the AnyConnect process. A successful exploit could allow the attacker to execute arbitrary code on the affected device with root privileges. To exploit this vulnerability, the attacker must have a valid account on the system.

ext/fts3/fts3.c in SQLite before 3.32.0 has a use-after-free in fts3EvalNextRow, related to the snippet feature.

Firejail before 0.9.64.4 allows attackers to bypass intended access restrictions because there is a TOCTOU race condition between a stat operation and an OverlayFS mount operation.

libffi requests an executable stack allowing attackers to more easily trigger arbitrary code execution by overwriting the stack. Please note that libffi is used by a number of other libraries. It was previously stated that this affects libffi version 3.2.1 but this appears to be incorrect. libffi prior to version 3.1 on 32 bit x86 systems was vulnerable, and upstream is believed to have fixed this issue in version 3.1.

An issue was discovered in the Linux kernel before 6.5.9, exploitable by local users with userspace access to MMIO registers. Incorrect access checking in the #VC handler and instruction emulation of the SEV-ES emulation of MMIO accesses could lead to arbitrary write access to kernel memory (and thus privilege escalation). This depends on a race condition through which userspace can replace an instruction before the #VC handler reads it.

When Apache Tomcat 9.0.0.M1 to 9.0.28, 8.5.0 to 8.5.47, 7.0.0 and 7.0.97 is configured with the JMX Remote Lifecycle Listener, a local attacker without access to the Tomcat process or configuration files is able to manipulate the RMI registry to perform a man-in-the-middle attack to capture user names and passwords used to access the JMX interface. The attacker can then use these credentials to access the JMX interface and gain complete control over the Tomcat instance.

A use-after-free flaw was found in mm/mempolicy.c in the memory management subsystem in the Linux Kernel. This issue is caused by a race between mbind() and VMA-locked page fault, and may allow a local attacker to crash the system or lead to a kernel information leak.

A double free bug in packet_set_ring() in net/packet/af_packet.c can be exploited by a local user through crafted syscalls to escalate privileges or deny service. We recommend upgrading kernel past the effected versions or rebuilding past ec6af094ea28f0f2dda1a6a33b14cd57e36a9755

A use-after-free vulnerability in the Linux kernel's af_unix component can be exploited to achieve local privilege escalation. The unix_stream_sendpage() function tries to add data to the last skb in the peer's recv queue without locking the queue. Thus there is a race where unix_stream_sendpage() could access an skb locklessly that is being released by garbage collection, resulting in use-after-free. We recommend upgrading past commit 790c2f9d15b594350ae9bca7b236f2b1859de02c.

A flaw was found in btrfs_get_root_ref in fs/btrfs/disk-io.c in the btrfs filesystem in the Linux Kernel due to a double decrement of the reference count. This issue may allow a local attacker with user privilege to crash the system or may lead to leaked internal kernel information.

Multiple stack-based buffer overflows in net/netfilter/ipvs/ip_vs_ctl.c in the Linux kernel before 2.6.33, when CONFIG_IP_VS is used, allow local users to gain privileges by leveraging the CAP_NET_ADMIN capability for (1) a getsockopt system call, related to the do_ip_vs_get_ctl function, or (2) a setsockopt system call, related to the do_ip_vs_set_ctl function.

When using Apache Tomcat versions 10.0.0-M1 to 10.0.0-M4, 9.0.0.M1 to 9.0.34, 8.5.0 to 8.5.54 and 7.0.0 to 7.0.103 if a) an attacker is able to control the contents and name of a file on the server; and b) the server is configured to use the PersistenceManager with a FileStore; and c) the PersistenceManager is configured with sessionAttributeValueClassNameFilter="null" (the default unless a SecurityManager is used) or a sufficiently lax filter to allow the attacker provided object to be deserialized; and d) the attacker knows the relative file path from the storage location used by FileStore to the file the attacker has control over; then, using a specifically crafted request, the attacker will be able to trigger remote code execution via deserialization of the file under their control. Note that all of conditions a) to d) must be true for the attack to succeed.

A use-after-free vulnerability in the Linux kernel's netfilter: nf_tables component can be exploited to achieve local privilege escalation. Due to a race condition between nf_tables netlink control plane transaction and nft_set element garbage collection, it is possible to underflow the reference counter causing a use-after-free vulnerability. We recommend upgrading past commit 3e91b0ebd994635df2346353322ac51ce84ce6d8.

io_uring UAF, Unix SCM garbage collection

Redis is an in-memory database that persists on disk. A specially crafted Lua script executing in Redis can trigger a heap overflow in the cjson library, and result with heap corruption and potentially remote code execution. The problem exists in all versions of Redis with Lua scripting support, starting from 2.6, and affects only authenticated and authorized users. The problem is fixed in versions 7.0.12, 6.2.13, and 6.0.20.

In the Linux kernel, the following vulnerability has been resolved: crypto: qat - resolve race condition during AER recovery During the PCI AER system's error recovery process, the kernel driver may encounter a race condition with freeing the reset_data structure's memory. If the device restart will take more than 10 seconds the function scheduling that restart will exit due to a timeout, and the reset_data structure will be freed. However, this data structure is used for completion notification after the restart is completed, which leads to a UAF bug. This results in a KFENCE bug notice. BUG: KFENCE: use-after-free read in adf_device_reset_worker+0x38/0xa0 [intel_qat] Use-after-free read at 0x00000000bc56fddf (in kfence-#142): adf_device_reset_worker+0x38/0xa0 [intel_qat] process_one_work+0x173/0x340 To resolve this race condition, the memory associated to the container of the work_struct is freed on the worker if the timeout expired, otherwise on the function that schedules the worker. The timeout detection can be done by checking if the caller is still waiting for completion or not by using completion_done() function.

Heap-based buffer overflow in drivers/net/macsec.c in the MACsec module in the Linux kernel through 4.10.12 allows attackers to cause a denial of service or possibly have unspecified other impact by leveraging the use of a MAX_SKB_FRAGS+1 size in conjunction with the NETIF_F_FRAGLIST feature, leading to an error in the skb_to_sgvec function.

The td-agent-builder plugin before 2020-12-18 for Fluentd allows attackers to gain privileges because the bin directory is writable by a user account, but a file in bin is executed as NT AUTHORITY\SYSTEM.

In systemd before v242-rc4, it was discovered that pam_systemd does not properly sanitize the environment before using the XDG_SEAT variable. It is possible for an attacker, in some particular configurations, to set a XDG_SEAT environment variable which allows for commands to be checked against polkit policies using the "allow_active" element rather than "allow_any".

runc through 1.0.0-rc9 has Incorrect Access Control leading to Escalation of Privileges, related to libcontainer/rootfs_linux.go. To exploit this, an attacker must be able to spawn two containers with custom volume-mount configurations, and be able to run custom images. (This vulnerability does not affect Docker due to an implementation detail that happens to block the attack.)

A possible unauthorized memory access flaw was found in the Linux kernel's cpu_entry_area mapping of X86 CPU data to memory, where a user may guess the location of exception stacks or other important data. Based on the previous CVE-2023-0597, the 'Randomize per-cpu entry area' feature was implemented in /arch/x86/mm/cpu_entry_area.c, which works through the init_cea_offsets() function when KASLR is enabled. However, despite this feature, there is still a risk of per-cpu entry area leaks. This issue could allow a local user to gain access to some important data with memory in an expected location and potentially escalate their privileges on the system.

An issue was discovered in the Linux kernel before 5.0.5. There is a use-after-free issue when hci_uart_register_dev() fails in hci_uart_set_proto() in drivers/bluetooth/hci_ldisc.c.

runc through 1.1.4 has Incorrect Access Control leading to Escalation of Privileges, related to libcontainer/rootfs_linux.go. To exploit this, an attacker must be able to spawn two containers with custom volume-mount configurations, and be able to run custom images. NOTE: this issue exists because of a CVE-2019-19921 regression.

In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: Fix UAF in blkcg_unpin_online() blkcg_unpin_online() walks up the blkcg hierarchy putting the online pin. To walk up, it uses blkcg_parent(blkcg) but it was calling that after blkcg_destroy_blkgs(blkcg) which could free the blkcg, leading to the following UAF: ================================================================== BUG: KASAN: slab-use-after-free in blkcg_unpin_online+0x15a/0x270 Read of size 8 at addr ffff8881057678c0 by task kworker/9:1/117 CPU: 9 UID: 0 PID: 117 Comm: kworker/9:1 Not tainted 6.13.0-rc1-work-00182-gb8f52214c61a-dirty #48 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS unknown 02/02/2022 Workqueue: cgwb_release cgwb_release_workfn Call Trace: <TASK> dump_stack_lvl+0x27/0x80 print_report+0x151/0x710 kasan_report+0xc0/0x100 blkcg_unpin_online+0x15a/0x270 cgwb_release_workfn+0x194/0x480 process_scheduled_works+0x71b/0xe20 worker_thread+0x82a/0xbd0 kthread+0x242/0x2c0 ret_from_fork+0x33/0x70 ret_from_fork_asm+0x1a/0x30 </TASK> ... Freed by task 1944: kasan_save_track+0x2b/0x70 kasan_save_free_info+0x3c/0x50 __kasan_slab_free+0x33/0x50 kfree+0x10c/0x330 css_free_rwork_fn+0xe6/0xb30 process_scheduled_works+0x71b/0xe20 worker_thread+0x82a/0xbd0 kthread+0x242/0x2c0 ret_from_fork+0x33/0x70 ret_from_fork_asm+0x1a/0x30 Note that the UAF is not easy to trigger as the free path is indirected behind a couple RCU grace periods and a work item execution. I could only trigger it with artifical msleep() injected in blkcg_unpin_online(). Fix it by reading the parent pointer before destroying the blkcg's blkg's.

In Docker Desktop before v4.29.0, an attacker who has gained access to the Docker Desktop VM through a container breakout can further escape to the host by passing extensions and dashboard related IPC messages. Docker Desktop v4.29.0 https://docs.docker.com/desktop/release-notes/#4290 fixes the issue on MacOS, Linux and Windows with Hyper-V backend. As exploitation requires "Allow only extensions distributed through the Docker Marketplace" to be disabled, Docker Desktop  v4.31.0 https://docs.docker.com/desktop/release-notes/#4310  additionally changes the default configuration to enable this setting by default.

An issue was discovered in the Linux kernel before 5.0.4. There is a use-after-free upon attempted read access to /proc/ioports after the ipmi_si module is removed, related to drivers/char/ipmi/ipmi_si_intf.c, drivers/char/ipmi/ipmi_si_mem_io.c, and drivers/char/ipmi/ipmi_si_port_io.c.

In the Linux kernel, the following vulnerability has been resolved: wifi: iwlegacy: Clear stale interrupts before resuming device iwl4965 fails upon resume from hibernation on my laptop. The reason seems to be a stale interrupt which isn't being cleared out before interrupts are enabled. We end up with a race beween the resume trying to bring things back up, and the restart work (queued form the interrupt handler) trying to bring things down. Eventually the whole thing blows up. Fix the problem by clearing out any stale interrupts before interrupts get enabled during resume. Here's a debug log of the indicent: [ 12.042589] ieee80211 phy0: il_isr ISR inta 0x00000080, enabled 0xaa00008b, fh 0x00000000 [ 12.042625] ieee80211 phy0: il4965_irq_tasklet inta 0x00000080, enabled 0x00000000, fh 0x00000000 [ 12.042651] iwl4965 0000:10:00.0: RF_KILL bit toggled to enable radio. [ 12.042653] iwl4965 0000:10:00.0: On demand firmware reload [ 12.042690] ieee80211 phy0: il4965_irq_tasklet End inta 0x00000000, enabled 0xaa00008b, fh 0x00000000, flags 0x00000282 [ 12.052207] ieee80211 phy0: il4965_mac_start enter [ 12.052212] ieee80211 phy0: il_prep_station Add STA to driver ID 31: ff:ff:ff:ff:ff:ff [ 12.052244] ieee80211 phy0: il4965_set_hw_ready hardware ready [ 12.052324] ieee80211 phy0: il_apm_init Init card's basic functions [ 12.052348] ieee80211 phy0: il_apm_init L1 Enabled; Disabling L0S [ 12.055727] ieee80211 phy0: il4965_load_bsm Begin load bsm [ 12.056140] ieee80211 phy0: il4965_verify_bsm Begin verify bsm [ 12.058642] ieee80211 phy0: il4965_verify_bsm BSM bootstrap uCode image OK [ 12.058721] ieee80211 phy0: il4965_load_bsm BSM write complete, poll 1 iterations [ 12.058734] ieee80211 phy0: __il4965_up iwl4965 is coming up [ 12.058737] ieee80211 phy0: il4965_mac_start Start UP work done. [ 12.058757] ieee80211 phy0: __il4965_down iwl4965 is going down [ 12.058761] ieee80211 phy0: il_scan_cancel_timeout Scan cancel timeout [ 12.058762] ieee80211 phy0: il_do_scan_abort Not performing scan to abort [ 12.058765] ieee80211 phy0: il_clear_ucode_stations Clearing ucode stations in driver [ 12.058767] ieee80211 phy0: il_clear_ucode_stations No active stations found to be cleared [ 12.058819] ieee80211 phy0: _il_apm_stop Stop card, put in low power state [ 12.058827] ieee80211 phy0: _il_apm_stop_master stop master [ 12.058864] ieee80211 phy0: il4965_clear_free_frames 0 frames on pre-allocated heap on clear. [ 12.058869] ieee80211 phy0: Hardware restart was requested [ 16.132299] iwl4965 0000:10:00.0: START_ALIVE timeout after 4000ms. [ 16.132303] ------------[ cut here ]------------ [ 16.132304] Hardware became unavailable upon resume. This could be a software issue prior to suspend or a hardware issue. [ 16.132338] WARNING: CPU: 0 PID: 181 at net/mac80211/util.c:1826 ieee80211_reconfig+0x8f/0x14b0 [mac80211] [ 16.132390] Modules linked in: ctr ccm sch_fq_codel xt_tcpudp xt_multiport xt_state iptable_filter iptable_nat nf_nat nf_conntrack nf_defrag_ipv4 ip_tables x_tables binfmt_misc joydev mousedev btusb btrtl btintel btbcm bluetooth ecdh_generic ecc iTCO_wdt i2c_dev iwl4965 iwlegacy coretemp snd_hda_codec_analog pcspkr psmouse mac80211 snd_hda_codec_generic libarc4 sdhci_pci cqhci sha256_generic sdhci libsha256 firewire_ohci snd_hda_intel snd_intel_dspcfg mmc_core snd_hda_codec snd_hwdep firewire_core led_class iosf_mbi snd_hda_core uhci_hcd lpc_ich crc_itu_t cfg80211 ehci_pci ehci_hcd snd_pcm usbcore mfd_core rfkill snd_timer snd usb_common soundcore video parport_pc parport intel_agp wmi intel_gtt backlight e1000e agpgart evdev [ 16.132456] CPU: 0 UID: 0 PID: 181 Comm: kworker/u8:6 Not tainted 6.11.0-cl+ #143 [ 16.132460] Hardware name: Hewlett-Packard HP Compaq 6910p/30BE, BIOS 68MCU Ver. F.19 07/06/2010 [ 16.132463] Workqueue: async async_run_entry_fn [ 16.132469] RIP: 0010:ieee80211_reconfig+0x8f/0x14b0 [mac80211] [ 16.132501] Code: da 02 00 0 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: ntb: ntb_hw_switchtec: Fix use after free vulnerability in switchtec_ntb_remove due to race condition In the switchtec_ntb_add function, it can call switchtec_ntb_init_sndev function, then &sndev->check_link_status_work is bound with check_link_status_work. switchtec_ntb_link_notification may be called to start the work. If we remove the module which will call switchtec_ntb_remove to make cleanup, it will free sndev through kfree(sndev), while the work mentioned above will be used. The sequence of operations that may lead to a UAF bug is as follows: CPU0 CPU1 | check_link_status_work switchtec_ntb_remove | kfree(sndev); | | if (sndev->link_force_down) | // use sndev Fix it by ensuring that the work is canceled before proceeding with the cleanup in switchtec_ntb_remove.

In the Linux kernel, the following vulnerability has been resolved: net: seeq: Fix use after free vulnerability in ether3 Driver Due to Race Condition In the ether3_probe function, a timer is initialized with a callback function ether3_ledoff, bound to &prev(dev)->timer. Once the timer is started, there is a risk of a race condition if the module or device is removed, triggering the ether3_remove function to perform cleanup. The sequence of operations that may lead to a UAF bug is as follows: CPU0 CPU1 | ether3_ledoff ether3_remove | free_netdev(dev); | put_devic | kfree(dev); | | ether3_outw(priv(dev)->regs.config2 |= CFG2_CTRLO, REG_CONFIG2); | // use dev Fix it by ensuring that the timer is canceled before proceeding with the cleanup in ether3_remove.

mm/mremap.c in the Linux kernel before 5.13.3 has a use-after-free via a stale TLB because an rmap lock is not held during a PUD move.

In the Linux kernel, the following vulnerability has been resolved: net/sched: Fix UAF when resolving a clash KASAN reports the following UAF: BUG: KASAN: slab-use-after-free in tcf_ct_flow_table_process_conn+0x12b/0x380 [act_ct] Read of size 1 at addr ffff888c07603600 by task handler130/6469 Call Trace: <IRQ> dump_stack_lvl+0x48/0x70 print_address_description.constprop.0+0x33/0x3d0 print_report+0xc0/0x2b0 kasan_report+0xd0/0x120 __asan_load1+0x6c/0x80 tcf_ct_flow_table_process_conn+0x12b/0x380 [act_ct] tcf_ct_act+0x886/0x1350 [act_ct] tcf_action_exec+0xf8/0x1f0 fl_classify+0x355/0x360 [cls_flower] __tcf_classify+0x1fd/0x330 tcf_classify+0x21c/0x3c0 sch_handle_ingress.constprop.0+0x2c5/0x500 __netif_receive_skb_core.constprop.0+0xb25/0x1510 __netif_receive_skb_list_core+0x220/0x4c0 netif_receive_skb_list_internal+0x446/0x620 napi_complete_done+0x157/0x3d0 gro_cell_poll+0xcf/0x100 __napi_poll+0x65/0x310 net_rx_action+0x30c/0x5c0 __do_softirq+0x14f/0x491 __irq_exit_rcu+0x82/0xc0 irq_exit_rcu+0xe/0x20 common_interrupt+0xa1/0xb0 </IRQ> <TASK> asm_common_interrupt+0x27/0x40 Allocated by task 6469: kasan_save_stack+0x38/0x70 kasan_set_track+0x25/0x40 kasan_save_alloc_info+0x1e/0x40 __kasan_krealloc+0x133/0x190 krealloc+0xaa/0x130 nf_ct_ext_add+0xed/0x230 [nf_conntrack] tcf_ct_act+0x1095/0x1350 [act_ct] tcf_action_exec+0xf8/0x1f0 fl_classify+0x355/0x360 [cls_flower] __tcf_classify+0x1fd/0x330 tcf_classify+0x21c/0x3c0 sch_handle_ingress.constprop.0+0x2c5/0x500 __netif_receive_skb_core.constprop.0+0xb25/0x1510 __netif_receive_skb_list_core+0x220/0x4c0 netif_receive_skb_list_internal+0x446/0x620 napi_complete_done+0x157/0x3d0 gro_cell_poll+0xcf/0x100 __napi_poll+0x65/0x310 net_rx_action+0x30c/0x5c0 __do_softirq+0x14f/0x491 Freed by task 6469: kasan_save_stack+0x38/0x70 kasan_set_track+0x25/0x40 kasan_save_free_info+0x2b/0x60 ____kasan_slab_free+0x180/0x1f0 __kasan_slab_free+0x12/0x30 slab_free_freelist_hook+0xd2/0x1a0 __kmem_cache_free+0x1a2/0x2f0 kfree+0x78/0x120 nf_conntrack_free+0x74/0x130 [nf_conntrack] nf_ct_destroy+0xb2/0x140 [nf_conntrack] __nf_ct_resolve_clash+0x529/0x5d0 [nf_conntrack] nf_ct_resolve_clash+0xf6/0x490 [nf_conntrack] __nf_conntrack_confirm+0x2c6/0x770 [nf_conntrack] tcf_ct_act+0x12ad/0x1350 [act_ct] tcf_action_exec+0xf8/0x1f0 fl_classify+0x355/0x360 [cls_flower] __tcf_classify+0x1fd/0x330 tcf_classify+0x21c/0x3c0 sch_handle_ingress.constprop.0+0x2c5/0x500 __netif_receive_skb_core.constprop.0+0xb25/0x1510 __netif_receive_skb_list_core+0x220/0x4c0 netif_receive_skb_list_internal+0x446/0x620 napi_complete_done+0x157/0x3d0 gro_cell_poll+0xcf/0x100 __napi_poll+0x65/0x310 net_rx_action+0x30c/0x5c0 __do_softirq+0x14f/0x491 The ct may be dropped if a clash has been resolved but is still passed to the tcf_ct_flow_table_process_conn function for further usage. This issue can be fixed by retrieving ct from skb again after confirming conntrack.

In the Linux kernel, the following vulnerability has been resolved: exec: Fix ToCToU between perm check and set-uid/gid usage When opening a file for exec via do_filp_open(), permission checking is done against the file's metadata at that moment, and on success, a file pointer is passed back. Much later in the execve() code path, the file metadata (specifically mode, uid, and gid) is used to determine if/how to set the uid and gid. However, those values may have changed since the permissions check, meaning the execution may gain unintended privileges. For example, if a file could change permissions from executable and not set-id: ---------x 1 root root 16048 Aug 7 13:16 target to set-id and non-executable: ---S------ 1 root root 16048 Aug 7 13:16 target it is possible to gain root privileges when execution should have been disallowed. While this race condition is rare in real-world scenarios, it has been observed (and proven exploitable) when package managers are updating the setuid bits of installed programs. Such files start with being world-executable but then are adjusted to be group-exec with a set-uid bit. For example, "chmod o-x,u+s target" makes "target" executable only by uid "root" and gid "cdrom", while also becoming setuid-root: -rwxr-xr-x 1 root cdrom 16048 Aug 7 13:16 target becomes: -rwsr-xr-- 1 root cdrom 16048 Aug 7 13:16 target But racing the chmod means users without group "cdrom" membership can get the permission to execute "target" just before the chmod, and when the chmod finishes, the exec reaches brpm_fill_uid(), and performs the setuid to root, violating the expressed authorization of "only cdrom group members can setuid to root". Re-check that we still have execute permissions in case the metadata has changed. It would be better to keep a copy from the perm-check time, but until we can do that refactoring, the least-bad option is to do a full inode_permission() call (under inode lock). It is understood that this is safe against dead-locks, but hardly optimal.

In the Linux kernel, the following vulnerability has been resolved: filelock: fix potential use-after-free in posix_lock_inode Light Hsieh reported a KASAN UAF warning in trace_posix_lock_inode(). The request pointer had been changed earlier to point to a lock entry that was added to the inode's list. However, before the tracepoint could fire, another task raced in and freed that lock. Fix this by moving the tracepoint inside the spinlock, which should ensure that this doesn't happen.

In the Linux kernel, the following vulnerability has been resolved: cachefiles: fix slab-use-after-free in cachefiles_withdraw_cookie() We got the following issue in our fault injection stress test: ================================================================== BUG: KASAN: slab-use-after-free in cachefiles_withdraw_cookie+0x4d9/0x600 Read of size 8 at addr ffff888118efc000 by task kworker/u78:0/109 CPU: 13 PID: 109 Comm: kworker/u78:0 Not tainted 6.8.0-dirty #566 Call Trace: <TASK> kasan_report+0x93/0xc0 cachefiles_withdraw_cookie+0x4d9/0x600 fscache_cookie_state_machine+0x5c8/0x1230 fscache_cookie_worker+0x91/0x1c0 process_one_work+0x7fa/0x1800 [...] Allocated by task 117: kmalloc_trace+0x1b3/0x3c0 cachefiles_acquire_volume+0xf3/0x9c0 fscache_create_volume_work+0x97/0x150 process_one_work+0x7fa/0x1800 [...] Freed by task 120301: kfree+0xf1/0x2c0 cachefiles_withdraw_cache+0x3fa/0x920 cachefiles_put_unbind_pincount+0x1f6/0x250 cachefiles_daemon_release+0x13b/0x290 __fput+0x204/0xa00 task_work_run+0x139/0x230 do_exit+0x87a/0x29b0 [...] ================================================================== Following is the process that triggers the issue: p1 | p2 ------------------------------------------------------------ fscache_begin_lookup fscache_begin_volume_access fscache_cache_is_live(fscache_cache) cachefiles_daemon_release cachefiles_put_unbind_pincount cachefiles_daemon_unbind cachefiles_withdraw_cache fscache_withdraw_cache fscache_set_cache_state(cache, FSCACHE_CACHE_IS_WITHDRAWN); cachefiles_withdraw_objects(cache) fscache_wait_for_objects(fscache) atomic_read(&fscache_cache->object_count) == 0 fscache_perform_lookup cachefiles_lookup_cookie cachefiles_alloc_object refcount_set(&object->ref, 1); object->volume = volume fscache_count_object(vcookie->cache); atomic_inc(&fscache_cache->object_count) cachefiles_withdraw_volumes cachefiles_withdraw_volume fscache_withdraw_volume __cachefiles_free_volume kfree(cachefiles_volume) fscache_cookie_state_machine cachefiles_withdraw_cookie cache = object->volume->cache; // cachefiles_volume UAF !!! After setting FSCACHE_CACHE_IS_WITHDRAWN, wait for all the cookie lookups to complete first, and then wait for fscache_cache->object_count == 0 to avoid the cookie exiting after the volume has been freed and triggering the above issue. Therefore call fscache_withdraw_volume() before calling cachefiles_withdraw_objects(). This way, after setting FSCACHE_CACHE_IS_WITHDRAWN, only the following two cases will occur: 1) fscache_begin_lookup fails in fscache_begin_volume_access(). 2) fscache_withdraw_volume() will ensure that fscache_count_object() has been executed before calling fscache_wait_for_objects().

In the Linux kernel, the following vulnerability has been resolved: gve: Account for stopped queues when reading NIC stats We now account for the fact that the NIC might send us stats for a subset of queues. Without this change, gve_get_ethtool_stats might make an invalid access on the priv->stats_report->stats array.

The fix for bug CVE-2020-9484 introduced a time of check, time of use vulnerability into Apache Tomcat 10.1.0-M1 to 10.1.0-M8, 10.0.0-M5 to 10.0.14, 9.0.35 to 9.0.56 and 8.5.55 to 8.5.73 that allowed a local attacker to perform actions with the privileges of the user that the Tomcat process is using. This issue is only exploitable when Tomcat is configured to persist sessions using the FileStore.

open-vm-tools contains a file descriptor hijack vulnerability in the vmware-user-suid-wrapper. A malicious actor with non-root privileges may be able to hijack the /dev/uinput file descriptor allowing them to simulate user inputs.

In the Linux kernel, the following vulnerability has been resolved: ipc/mqueue, msg, sem: avoid relying on a stack reference past its expiry do_mq_timedreceive calls wq_sleep with a stack local address. The sender (do_mq_timedsend) uses this address to later call pipelined_send. This leads to a very hard to trigger race where a do_mq_timedreceive call might return and leave do_mq_timedsend to rely on an invalid address, causing the following crash: RIP: 0010:wake_q_add_safe+0x13/0x60 Call Trace: __x64_sys_mq_timedsend+0x2a9/0x490 do_syscall_64+0x80/0x680 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f5928e40343 The race occurs as: 1. do_mq_timedreceive calls wq_sleep with the address of `struct ext_wait_queue` on function stack (aliased as `ewq_addr` here) - it holds a valid `struct ext_wait_queue *` as long as the stack has not been overwritten. 2. `ewq_addr` gets added to info->e_wait_q[RECV].list in wq_add, and do_mq_timedsend receives it via wq_get_first_waiter(info, RECV) to call __pipelined_op. 3. Sender calls __pipelined_op::smp_store_release(&this->state, STATE_READY). Here is where the race window begins. (`this` is `ewq_addr`.) 4. If the receiver wakes up now in do_mq_timedreceive::wq_sleep, it will see `state == STATE_READY` and break. 5. do_mq_timedreceive returns, and `ewq_addr` is no longer guaranteed to be a `struct ext_wait_queue *` since it was on do_mq_timedreceive's stack. (Although the address may not get overwritten until another function happens to touch it, which means it can persist around for an indefinite time.) 6. do_mq_timedsend::__pipelined_op() still believes `ewq_addr` is a `struct ext_wait_queue *`, and uses it to find a task_struct to pass to the wake_q_add_safe call. In the lucky case where nothing has overwritten `ewq_addr` yet, `ewq_addr->task` is the right task_struct. In the unlucky case, __pipelined_op::wake_q_add_safe gets handed a bogus address as the receiver's task_struct causing the crash. do_mq_timedsend::__pipelined_op() should not dereference `this` after setting STATE_READY, as the receiver counterpart is now free to return. Change __pipelined_op to call wake_q_add_safe on the receiver's task_struct returned by get_task_struct, instead of dereferencing `this` which sits on the receiver's stack. As Manfred pointed out, the race potentially also exists in ipc/msg.c::expunge_all and ipc/sem.c::wake_up_sem_queue_prepare. Fix those in the same way.

In the Linux kernel, the following vulnerability has been resolved: ALSA: seq: Fix race of snd_seq_timer_open() The timer instance per queue is exclusive, and snd_seq_timer_open() should have managed the concurrent accesses. It looks as if it's checking the already existing timer instance at the beginning, but it's not right, because there is no protection, hence any later concurrent call of snd_seq_timer_open() may override the timer instance easily. This may result in UAF, as the leftover timer instance can keep running while the queue itself gets closed, as spotted by syzkaller recently. For avoiding the race, add a proper check at the assignment of tmr->timeri again, and return -EBUSY if it's been already registered.

In the Linux kernel, the following vulnerability has been resolved: mm/damon/dbgfs: protect targets destructions with kdamond_lock DAMON debugfs interface iterates current monitoring targets in 'dbgfs_target_ids_read()' while holding the corresponding 'kdamond_lock'. However, it also destructs the monitoring targets in 'dbgfs_before_terminate()' without holding the lock. This can result in a use_after_free bug. This commit avoids the race by protecting the destruction with the corresponding 'kdamond_lock'.

A flaw was found in the way the dumpable flag setting was handled when certain SUID binaries executed its descendants. The prerequisite is a SUID binary that sets real UID equal to effective UID, and real GID equal to effective GID. The descendant will then have a dumpable value set to 1. As a result, if the descendant process crashes and core_pattern is set to a relative value, its core dump is stored in the current directory with uid:gid permissions. An unprivileged local user with eligible root SUID binary could use this flaw to place core dumps into root-owned directories, potentially resulting in escalation of privileges.

In the Linux kernel, the following vulnerability has been resolved: ALSA: sh: aica: reorder cleanup operations to avoid UAF bugs The dreamcastcard->timer could schedule the spu_dma_work and the spu_dma_work could also arm the dreamcastcard->timer. When the snd_pcm_substream is closing, the aica_channel will be deallocated. But it could still be dereferenced in the worker thread. The reason is that del_timer() will return directly regardless of whether the timer handler is running or not and the worker could be rescheduled in the timer handler. As a result, the UAF bug will happen. The racy situation is shown below: (Thread 1) | (Thread 2) snd_aicapcm_pcm_close() | ... | run_spu_dma() //worker | mod_timer() flush_work() | del_timer() | aica_period_elapsed() //timer kfree(dreamcastcard->channel) | schedule_work() | run_spu_dma() //worker ... | dreamcastcard->channel-> //USE In order to mitigate this bug and other possible corner cases, call mod_timer() conditionally in run_spu_dma(), then implement PCM sync_stop op to cancel both the timer and worker. The sync_stop op will be called from PCM core appropriately when needed.

The __oom_reap_task_mm function in mm/oom_kill.c in the Linux kernel before 4.14.4 mishandles gather operations, which allows attackers to cause a denial of service (TLB entry leak or use-after-free) or possibly have unspecified other impact by triggering a copy_to_user call within a certain time window.

The init_new_context function in arch/x86/include/asm/mmu_context.h in the Linux kernel before 4.12.10 does not correctly handle errors from LDT table allocation when forking a new process, allowing a local attacker to achieve a use-after-free or possibly have unspecified other impact by running a specially crafted program. This vulnerability only affected kernels built with CONFIG_MODIFY_LDT_SYSCALL=y.

This vulnerability allows local attackers to escalate privileges on affected installations of Linux Kernel 5.11.15. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. The specific flaw exists within the handling of eBPF programs. The issue results from the lack of proper validation of user-supplied eBPF programs prior to executing them. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of the kernel. Was ZDI-CAN-13661.