A use-after-free vulnerability in the Linux Kernel io_uring subsystem can be exploited to achieve local privilege escalation. Both io_install_fixed_file and its callers call fput in a file in case of an error, causing a reference underflow which leads to a use-after-free vulnerability. We recommend upgrading past commit 9d94c04c0db024922e886c9fd429659f22f48ea4.

In the Linux kernel, the following vulnerability has been resolved: macsec: Fix use-after-free while sending the offloading packet KASAN reports the following UAF. The metadata_dst, which is used to store the SCI value for macsec offload, is already freed by metadata_dst_free() in macsec_free_netdev(), while driver still use it for sending the packet. To fix this issue, dst_release() is used instead to release metadata_dst. So it is not freed instantly in macsec_free_netdev() if still referenced by skb. BUG: KASAN: slab-use-after-free in mlx5e_xmit+0x1e8f/0x4190 [mlx5_core] Read of size 2 at addr ffff88813e42e038 by task kworker/7:2/714 [...] Workqueue: mld mld_ifc_work Call Trace: <TASK> dump_stack_lvl+0x51/0x60 print_report+0xc1/0x600 kasan_report+0xab/0xe0 mlx5e_xmit+0x1e8f/0x4190 [mlx5_core] dev_hard_start_xmit+0x120/0x530 sch_direct_xmit+0x149/0x11e0 __qdisc_run+0x3ad/0x1730 __dev_queue_xmit+0x1196/0x2ed0 vlan_dev_hard_start_xmit+0x32e/0x510 [8021q] dev_hard_start_xmit+0x120/0x530 __dev_queue_xmit+0x14a7/0x2ed0 macsec_start_xmit+0x13e9/0x2340 dev_hard_start_xmit+0x120/0x530 __dev_queue_xmit+0x14a7/0x2ed0 ip6_finish_output2+0x923/0x1a70 ip6_finish_output+0x2d7/0x970 ip6_output+0x1ce/0x3a0 NF_HOOK.constprop.0+0x15f/0x190 mld_sendpack+0x59a/0xbd0 mld_ifc_work+0x48a/0xa80 process_one_work+0x5aa/0xe50 worker_thread+0x79c/0x1290 kthread+0x28f/0x350 ret_from_fork+0x2d/0x70 ret_from_fork_asm+0x11/0x20 </TASK> Allocated by task 3922: kasan_save_stack+0x20/0x40 kasan_save_track+0x10/0x30 __kasan_kmalloc+0x77/0x90 __kmalloc_noprof+0x188/0x400 metadata_dst_alloc+0x1f/0x4e0 macsec_newlink+0x914/0x1410 __rtnl_newlink+0xe08/0x15b0 rtnl_newlink+0x5f/0x90 rtnetlink_rcv_msg+0x667/0xa80 netlink_rcv_skb+0x12c/0x360 netlink_unicast+0x551/0x770 netlink_sendmsg+0x72d/0xbd0 __sock_sendmsg+0xc5/0x190 ____sys_sendmsg+0x52e/0x6a0 ___sys_sendmsg+0xeb/0x170 __sys_sendmsg+0xb5/0x140 do_syscall_64+0x4c/0x100 entry_SYSCALL_64_after_hwframe+0x4b/0x53 Freed by task 4011: kasan_save_stack+0x20/0x40 kasan_save_track+0x10/0x30 kasan_save_free_info+0x37/0x50 poison_slab_object+0x10c/0x190 __kasan_slab_free+0x11/0x30 kfree+0xe0/0x290 macsec_free_netdev+0x3f/0x140 netdev_run_todo+0x450/0xc70 rtnetlink_rcv_msg+0x66f/0xa80 netlink_rcv_skb+0x12c/0x360 netlink_unicast+0x551/0x770 netlink_sendmsg+0x72d/0xbd0 __sock_sendmsg+0xc5/0x190 ____sys_sendmsg+0x52e/0x6a0 ___sys_sendmsg+0xeb/0x170 __sys_sendmsg+0xb5/0x140 do_syscall_64+0x4c/0x100 entry_SYSCALL_64_after_hwframe+0x4b/0x53

The ATI Rage 128 (aka r128) driver in the Linux kernel before 2.6.31-git11 does not properly verify Concurrent Command Engine (CCE) state initialization, which allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly gain privileges via unspecified ioctl calls.

The collect_rx_frame function in drivers/isdn/hisax/hfc_usb.c in the Linux kernel before 2.6.32-rc7 allows attackers to have an unspecified impact via a crafted HDLC packet that arrives over ISDN and triggers a buffer under-read.

In Sudo before 1.9.12p2, the sudoedit (aka -e) feature mishandles extra arguments passed in the user-provided environment variables (SUDO_EDITOR, VISUAL, and EDITOR), allowing a local attacker to append arbitrary entries to the list of files to process. This can lead to privilege escalation. Affected versions are 1.8.0 through 1.9.12.p1. The problem exists because a user-specified editor may contain a "--" argument that defeats a protection mechanism, e.g., an EDITOR='vim -- /path/to/extra/file' value.

Integer overflow in the kvm_dev_ioctl_get_supported_cpuid function in arch/x86/kvm/x86.c in the KVM subsystem in the Linux kernel before 2.6.31.4 allows local users to have an unspecified impact via a KVM_GET_SUPPORTED_CPUID request to the kvm_arch_dev_ioctl function.

The connector layer in the Linux kernel before 2.6.31.5 does not require the CAP_SYS_ADMIN capability for certain interaction with the (1) uvesafb, (2) pohmelfs, (3) dst, or (4) dm subsystem, which allows local users to bypass intended access restrictions and gain privileges via calls to functions in these subsystems.

An issue was discovered in the Linux kernel through 5.10.11. PI futexes have a kernel stack use-after-free during fault handling, allowing local users to execute code in the kernel, aka CID-34b1a1ce1458.

The g_file_copy function in glib 2.0 sets the permissions of a target file to the permissions of a symbolic link (777), which allows user-assisted local users to modify files of other users, as demonstrated by using Nautilus to modify the permissions of the user home directory.

Linux kreatecd trusts a user-supplied path that is used to find the cdrecord program, allowing local users to gain root privileges.

/bin/login in shadow 4.0.18.1 in Debian GNU/Linux, and probably other Linux distributions, allows local users in the utmp group to overwrite arbitrary files via a symlink attack on a temporary file referenced in a line (aka ut_line) field in a utmp entry.

A flaw was found in libcaca v0.99.beta19. A buffer overflow issue in caca_resize function in libcaca/caca/canvas.c may lead to local execution of arbitrary code in the user context.

A vulnerability was found in compare_netdev_and_ip in drivers/infiniband/core/cma.c in RDMA in the Linux Kernel. The improper cleanup results in out-of-boundary read, where a local user can utilize this problem to crash the system or escalation of privilege.

The bpf verifier in the Linux kernel did not properly handle mod32 destination register truncation when the source register was known to be 0. A local attacker with the ability to load bpf programs could use this gain out-of-bounds reads in kernel memory leading to information disclosure (kernel memory), and possibly out-of-bounds writes that could potentially lead to code execution. This issue was addressed in the upstream kernel in commit 9b00f1b78809 ("bpf: Fix truncation handling for mod32 dst reg wrt zero") and in Linux stable kernels 5.11.2, 5.10.19, and 5.4.101.

The load_flat_shared_library function in fs/binfmt_flat.c in the flat subsystem in the Linux kernel before 2.6.31-rc6 allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact by executing a shared flat binary, which triggers an access of an "uninitialized cred pointer."

The Linux kernel before 2.6.31-rc7 does not properly prevent mmap operations that target page zero and other low memory addresses, which allows local users to gain privileges by exploiting NULL pointer dereference vulnerabilities, related to (1) the default configuration of the allow_unconfined_mmap_low boolean in SELinux on Red Hat Enterprise Linux (RHEL) 5, (2) an error that causes allow_unconfined_mmap_low to be ignored in the unconfined_t domain, (3) lack of a requirement for the CAP_SYS_RAWIO capability for these mmap operations, and (4) interaction between the mmap_min_addr protection mechanism and certain application programs.

The udp_sendmsg function in the UDP implementation in (1) net/ipv4/udp.c and (2) net/ipv6/udp.c in the Linux kernel before 2.6.19 allows local users to gain privileges or cause a denial of service (NULL pointer dereference and system crash) via vectors involving the MSG_MORE flag and a UDP socket.

Buffer overflow in kon program in Kanji on Console (KON) package on Linux may allow local users to gain root privileges via a long -StartupMessage parameter.

The Linux kernel 2.6.0 through 2.6.30.4, and 2.4.4 through 2.4.37.4, does not initialize all function pointers for socket operations in proto_ops structures, which allows local users to trigger a NULL pointer dereference and gain privileges by using mmap to map page zero, placing arbitrary code on this page, and then invoking an unavailable operation, as demonstrated by the sendpage operation (sock_sendpage function) on a PF_PPPOX socket.

Off-by-one error in the options_write function in drivers/misc/sgi-gru/gruprocfs.c in the SGI GRU driver in the Linux kernel 2.6.30.2 and earlier on ia64 and x86 platforms might allow local users to overwrite arbitrary memory locations and gain privileges via a crafted count argument, which triggers a stack-based buffer overflow.

The init_posix_timers function in kernel/posix-timers.c in the Linux kernel before 2.6.31-rc6 allows local users to cause a denial of service (OOPS) or possibly gain privileges via a CLOCK_MONOTONIC_RAW clock_nanosleep call that triggers a NULL pointer dereference.

The specific flaw exists within the DPT I2O Controller driver. The issue results from the lack of proper locking when performing operations on an object. An attacker can leverage this in conjunction with other vulnerabilities to escalate privileges and execute arbitrary code in the context of the kernel.

When Octopus Tentacle is installed on a Linux operating system, the systemd service file permissions are misconfigured. This could lead to a local unprivileged user modifying the contents of the systemd service file to gain privileged access.

A flaw was found in the Linux kernel's udmabuf device driver. The specific flaw exists within a fault handler. The issue results from the lack of proper validation of user-supplied data, which can result in a memory access past the end of an array. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of the kernel.

A use-after-free vulnerability in the Linux Kernel io_uring system can be exploited to achieve local privilege escalation. The io_file_get_fixed function lacks the presence of ctx->uring_lock which can lead to a Use-After-Free vulnerability due a race condition with fixed files getting unregistered. We recommend upgrading past commit da24142b1ef9fd5d36b76e36bab328a5b27523e8.

In the Linux kernel 5.11 through 5.12.2, isotp_setsockopt in net/can/isotp.c allows privilege escalation to root by leveraging a use-after-free. (This does not affect earlier versions that lack CAN ISOTP SF_BROADCAST support.)

In the Linux kernel before 5.12.4, net/bluetooth/hci_event.c has a use-after-free when destroying an hci_chan, aka CID-5c4c8c954409. This leads to writing an arbitrary value.

The personality subsystem in the Linux kernel before 2.6.31-rc3 has a PER_CLEAR_ON_SETID setting that does not clear the ADDR_COMPAT_LAYOUT and MMAP_PAGE_ZERO flags when executing a setuid or setgid program, which makes it easier for local users to leverage the details of memory usage to (1) conduct NULL pointer dereference attacks, (2) bypass the mmap_min_addr protection mechanism, or (3) defeat address space layout randomization (ASLR).

pt_chown in the glibc package before 2.19-18+deb8u4 on Debian jessie; the elibc package before 2.15-0ubuntu10.14 on Ubuntu 12.04 LTS and before 2.19-0ubuntu6.8 on Ubuntu 14.04 LTS; and the glibc package before 2.21-0ubuntu4.2 on Ubuntu 15.10 and before 2.23-0ubuntu1 on Ubuntu 16.04 LTS and 16.10 lacks a namespace check associated with file-descriptor passing, which allows local users to capture keystrokes and spoof data, and possibly gain privileges, via pts read and write operations, related to debian/sysdeps/linux.mk. NOTE: this is not considered a vulnerability in the upstream GNU C Library because the upstream documentation has a clear security recommendation against the --enable-pt_chown option.

The netfilter subsystem in the Linux kernel through 4.5.2 does not validate certain offset fields, which allows local users to gain privileges or cause a denial of service (heap memory corruption) via an IPT_SO_SET_REPLACE setsockopt call.

udev before 1.4.1 does not verify whether a NETLINK message originates from kernel space, which allows local users to gain privileges by sending a NETLINK message from user space.

Insufficient validation in the IOCTL (Input Output Control) input buffer in AMD uProf may allow an authenticated user to load an unsigned driver potentially leading to arbitrary kernel execution.

Unspecified vulnerability in the dpwinsup module (dpwinsup.dll) for dpwingad (dpwingad.exe) in HP Data Protector Express and Express SSE 3.x before build 47065, and Express and Express SSE 4.x before build 46537, allows remote attackers to cause a denial of service (application crash) or read portions of memory via one or more crafted packets.

The Apache Log4j hotpatch package before log4j-cve-2021-44228-hotpatch-1.1-13 didn’t mimic the permissions of the JVM being patched, allowing it to escalate privileges.

The __switch_to function in arch/x86/kernel/process_64.c in the Linux kernel does not properly context-switch IOPL on 64-bit PV Xen guests, which allows local guest OS users to gain privileges, cause a denial of service (guest OS crash), or obtain sensitive information by leveraging I/O port access.

Niels Provos Systrace 1.6f and earlier on the x86_64 Linux platform allows local users to bypass intended access restrictions by making a 32-bit syscall with a syscall number that corresponds to a policy-compliant 64-bit syscall, related to race conditions that occur in monitoring 64-bit processes.

The adreno_perfcounter_query_group function in drivers/gpu/msm/adreno_perfcounter.c in the Adreno GPU driver for the Linux kernel 3.x, as used in Qualcomm Innovation Center (QuIC) Android contributions for MSM devices and other products, uses an incorrect integer data type, which allows attackers to cause a denial of service (integer overflow, heap-based buffer overflow, and incorrect memory allocation) or possibly have unspecified other impact via a crafted IOCTL_KGSL_PERFCOUNTER_QUERY ioctl call.

rssh version 2.3.4 contains a CWE-77: Improper Neutralization of Special Elements used in a Command ('Command Injection') vulnerability in allowscp permission that can result in Local command execution. This attack appear to be exploitable via An authorized SSH user with the allowscp permission.

In the Linux kernel, the following vulnerability has been resolved: nfc: nci: add flush_workqueue to prevent uaf Our detector found a concurrent use-after-free bug when detaching an NCI device. The main reason for this bug is the unexpected scheduling between the used delayed mechanism (timer and workqueue). The race can be demonstrated below: Thread-1 Thread-2 | nci_dev_up() | nci_open_device() | __nci_request(nci_reset_req) | nci_send_cmd | queue_work(cmd_work) nci_unregister_device() | nci_close_device() | ... del_timer_sync(cmd_timer)[1] | ... | Worker nci_free_device() | nci_cmd_work() kfree(ndev)[3] | mod_timer(cmd_timer)[2] In short, the cleanup routine thought that the cmd_timer has already been detached by [1] but the mod_timer can re-attach the timer [2], even it is already released [3], resulting in UAF. This UAF is easy to trigger, crash trace by POC is like below [ 66.703713] ================================================================== [ 66.703974] BUG: KASAN: use-after-free in enqueue_timer+0x448/0x490 [ 66.703974] Write of size 8 at addr ffff888009fb7058 by task kworker/u4:1/33 [ 66.703974] [ 66.703974] CPU: 1 PID: 33 Comm: kworker/u4:1 Not tainted 5.18.0-rc2 #5 [ 66.703974] Workqueue: nfc2_nci_cmd_wq nci_cmd_work [ 66.703974] Call Trace: [ 66.703974] <TASK> [ 66.703974] dump_stack_lvl+0x57/0x7d [ 66.703974] print_report.cold+0x5e/0x5db [ 66.703974] ? enqueue_timer+0x448/0x490 [ 66.703974] kasan_report+0xbe/0x1c0 [ 66.703974] ? enqueue_timer+0x448/0x490 [ 66.703974] enqueue_timer+0x448/0x490 [ 66.703974] __mod_timer+0x5e6/0xb80 [ 66.703974] ? mark_held_locks+0x9e/0xe0 [ 66.703974] ? try_to_del_timer_sync+0xf0/0xf0 [ 66.703974] ? lockdep_hardirqs_on_prepare+0x17b/0x410 [ 66.703974] ? queue_work_on+0x61/0x80 [ 66.703974] ? lockdep_hardirqs_on+0xbf/0x130 [ 66.703974] process_one_work+0x8bb/0x1510 [ 66.703974] ? lockdep_hardirqs_on_prepare+0x410/0x410 [ 66.703974] ? pwq_dec_nr_in_flight+0x230/0x230 [ 66.703974] ? rwlock_bug.part.0+0x90/0x90 [ 66.703974] ? _raw_spin_lock_irq+0x41/0x50 [ 66.703974] worker_thread+0x575/0x1190 [ 66.703974] ? process_one_work+0x1510/0x1510 [ 66.703974] kthread+0x2a0/0x340 [ 66.703974] ? kthread_complete_and_exit+0x20/0x20 [ 66.703974] ret_from_fork+0x22/0x30 [ 66.703974] </TASK> [ 66.703974] [ 66.703974] Allocated by task 267: [ 66.703974] kasan_save_stack+0x1e/0x40 [ 66.703974] __kasan_kmalloc+0x81/0xa0 [ 66.703974] nci_allocate_device+0xd3/0x390 [ 66.703974] nfcmrvl_nci_register_dev+0x183/0x2c0 [ 66.703974] nfcmrvl_nci_uart_open+0xf2/0x1dd [ 66.703974] nci_uart_tty_ioctl+0x2c3/0x4a0 [ 66.703974] tty_ioctl+0x764/0x1310 [ 66.703974] __x64_sys_ioctl+0x122/0x190 [ 66.703974] do_syscall_64+0x3b/0x90 [ 66.703974] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 66.703974] [ 66.703974] Freed by task 406: [ 66.703974] kasan_save_stack+0x1e/0x40 [ 66.703974] kasan_set_track+0x21/0x30 [ 66.703974] kasan_set_free_info+0x20/0x30 [ 66.703974] __kasan_slab_free+0x108/0x170 [ 66.703974] kfree+0xb0/0x330 [ 66.703974] nfcmrvl_nci_unregister_dev+0x90/0xd0 [ 66.703974] nci_uart_tty_close+0xdf/0x180 [ 66.703974] tty_ldisc_kill+0x73/0x110 [ 66.703974] tty_ldisc_hangup+0x281/0x5b0 [ 66.703974] __tty_hangup.part.0+0x431/0x890 [ 66.703974] tty_release+0x3a8/0xc80 [ 66.703974] __fput+0x1f0/0x8c0 [ 66.703974] task_work_run+0xc9/0x170 [ 66.703974] exit_to_user_mode_prepare+0x194/0x1a0 [ 66.703974] syscall_exit_to_user_mode+0x19/0x50 [ 66.703974] do_syscall_64+0x48/0x90 [ 66.703974] entry_SYSCALL_64_after_hwframe+0x44/0x ---truncated---

In drivers/pci/hotplug/rpadlpar_sysfs.c in the Linux kernel through 5.11.8, the RPA PCI Hotplug driver has a user-tolerable buffer overflow when writing a new device name to the driver from userspace, allowing userspace to write data to the kernel stack frame directly. This occurs because add_slot_store and remove_slot_store mishandle drc_name '\0' termination, aka CID-cc7a0bb058b8.