The eBPF RINGBUF bpf_ringbuf_reserve() function in the Linux kernel did not check that the allocated size was smaller than the ringbuf size, allowing an attacker to perform out-of-bounds writes within the kernel and therefore, arbitrary code execution. This issue was fixed via commit 4b81ccebaeee ("bpf, ringbuf: Deny reserve of buffers larger than ringbuf") (v5.13-rc4) and backported to the stable kernels in v5.12.4, v5.11.21, and v5.10.37. It was introduced via 457f44363a88 ("bpf: Implement BPF ring buffer and verifier support for it") (v5.8-rc1).

The KEYS subsystem in the Linux kernel before 4.4 allows local users to gain privileges or cause a denial of service (BUG) via crafted keyctl commands that negatively instantiate a key, related to security/keys/encrypted-keys/encrypted.c, security/keys/trusted.c, and security/keys/user_defined.c.

The overlayfs implementation in the linux kernel did not properly validate with respect to user namespaces the setting of file capabilities on files in an underlying file system. Due to the combination of unprivileged user namespaces along with a patch carried in the Ubuntu kernel to allow unprivileged overlay mounts, an attacker could use this to gain elevated privileges.

The eBPF ALU32 bounds tracking for bitwise ops (AND, OR and XOR) in the Linux kernel did not properly update 32-bit bounds, which could be turned into out of bounds reads and writes in the Linux kernel and therefore, arbitrary code execution. This issue was fixed via commit 049c4e13714e ("bpf: Fix alu32 const subreg bound tracking on bitwise operations") (v5.13-rc4) and backported to the stable kernels in v5.12.4, v5.11.21, and v5.10.37. The AND/OR issues were introduced by commit 3f50f132d840 ("bpf: Verifier, do explicit ALU32 bounds tracking") (5.7-rc1) and the XOR variant was introduced by 2921c90d4718 ("bpf:Fix a verifier failure with xor") ( 5.10-rc1).

The io_uring subsystem in the Linux kernel allowed the MAX_RW_COUNT limit to be bypassed in the PROVIDE_BUFFERS operation, which led to negative values being usedin mem_rw when reading /proc/<PID>/mem. This could be used to create a heap overflow leading to arbitrary code execution in the kernel. It was addressed via commit d1f82808877b ("io_uring: truncate lengths larger than MAX_RW_COUNT on provide buffers") (v5.13-rc1) and backported to the stable kernels in v5.12.4, v5.11.21, and v5.10.37. It was introduced in ddf0322db79c ("io_uring: add IORING_OP_PROVIDE_BUFFERS") (v5.7-rc1).

Shiftfs, an out-of-tree stacking file system included in Ubuntu Linux kernels, did not properly handle faults occurring during copy_from_user() correctly. These could lead to either a double-free situation or memory not being freed at all. An attacker could use this to cause a denial of service (kernel memory exhaustion) or gain privileges via executing arbitrary code. AKA ZDI-CAN-13562.

Integer overflow in the drm_mode_dirtyfb_ioctl function in drivers/gpu/drm/drm_crtc.c in the Direct Rendering Manager (DRM) subsystem in the Linux kernel before 3.1.5 allows local users to gain privileges or cause a denial of service (memory corruption) via a crafted ioctl call.

The start_thread function in arch/powerpc/kernel/process.c in the Linux kernel through 4.6.3 on powerpc platforms mishandles transactional state, which allows local users to cause a denial of service (invalid process state or TM Bad Thing exception, and system crash) or possibly have unspecified other impact by starting and suspending a transaction before an exec system call.

Multiple heap-based buffer overflows in the hiddev_ioctl_usage function in drivers/hid/usbhid/hiddev.c in the Linux kernel through 4.6.3 allow local users to cause a denial of service or possibly have unspecified other impact via a crafted (1) HIDIOCGUSAGES or (2) HIDIOCSUSAGES ioctl call.

Use-after-free vulnerability in mm/percpu.c in the Linux kernel through 4.6 allows local users to cause a denial of service (BUG) or possibly have unspecified other impact via crafted use of the mmap and bpf system calls.

The compat IPT_SO_SET_REPLACE and IP6T_SO_SET_REPLACE setsockopt implementations in the netfilter subsystem in the Linux kernel before 4.6.3 allow local users to gain privileges or cause a denial of service (memory corruption) by leveraging in-container root access to provide a crafted offset value that triggers an unintended decrement.

Use-after-free vulnerability in drivers/net/ppp/ppp_generic.c in the Linux kernel before 4.5.2 allows local users to cause a denial of service (memory corruption and system crash, or spinlock) or possibly have unspecified other impact by removing a network namespace, related to the ppp_register_net_channel and ppp_unregister_channel functions.

The tipc_nl_publ_dump function in net/tipc/socket.c in the Linux kernel through 4.6 does not verify socket existence, which allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact via a dumpit operation.

The InfiniBand (aka IB) stack in the Linux kernel before 4.5.3 incorrectly relies on the write system call, which allows local users to cause a denial of service (kernel memory write operation) or possibly have unspecified other impact via a uAPI interface.

Race condition in mm/gup.c in the Linux kernel 2.x through 4.x before 4.8.3 allows local users to gain privileges by leveraging incorrect handling of a copy-on-write (COW) feature to write to a read-only memory mapping, as exploited in the wild in October 2016, aka "Dirty COW."

In binder_alloc_free_page of binder_alloc.c, there is a possible double free due to improper locking. This could lead to local escalation of privilege in the kernel with no additional execution privileges needed. User interaction is not needed for exploitation. Product: Android. Versions: Android kernel. Android ID: A-120025196.

In the Linux kernel before 5.3.4, a reference count usage error in the fib6_rule_suppress() function in the fib6 suppression feature of net/ipv6/fib6_rules.c, when handling the FIB_LOOKUP_NOREF flag, can be exploited by a local attacker to corrupt memory, aka CID-ca7a03c41753.

The get_rock_ridge_filename function in fs/isofs/rock.c in the Linux kernel before 4.5.5 mishandles NM (aka alternate name) entries containing \0 characters, which allows local users to obtain sensitive information from kernel memory or possibly have unspecified other impact via a crafted isofs filesystem.

Privilege escalation vulnerability in MicroK8s allows a low privilege user with local access to obtain root access to the host by provisioning a privileged container. Fixed in MicroK8s 1.15.3.

pam-python before 1.0.7-1 has an issue in regard to the default environment variable handling of Python, which could allow for local root escalation in certain PAM setups.

An issue was discovered in the Linux kernel before 5.2.3. An out of bounds access exists in the function hclge_tm_schd_mode_vnet_base_cfg in the file drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_tm.c.

Unspecified vulnerability in Oracle Java SE 6u85, 7u72, and 8u25 allows remote attackers to affect confidentiality, integrity, and availability via vectors related to JAX-WS.

There is heap-based buffer overflow in Linux kernel, all versions up to, excluding 5.3, in the marvell wifi chip driver in Linux kernel, that allows local users to cause a denial of service(system crash) or possibly execute arbitrary code.

An out-of-bounds access issue was found in the Linux kernel, all versions through 5.3, in the way Linux kernel's KVM hypervisor implements the Coalesced MMIO write operation. It operates on an MMIO ring buffer 'struct kvm_coalesced_mmio' object, wherein write indices 'ring->first' and 'ring->last' value could be supplied by a host user-space process. An unprivileged host user or process with access to '/dev/kvm' device could use this flaw to crash the host kernel, resulting in a denial of service or potentially escalating privileges on the system.

A buffer overflow flaw was found, in versions from 2.6.34 to 5.2.x, in the way Linux kernel's vhost functionality that translates virtqueue buffers to IOVs, logged the buffer descriptors during migration. A privileged guest user able to pass descriptors with invalid length to the host when migration is underway, could use this flaw to increase their privileges on the host.

It was discovered that the get_pid_info() function in data/apport did not properly parse the /proc/pid/status file from the kernel.

In the Linux kernel before 5.1.17, ptrace_link in kernel/ptrace.c mishandles the recording of the credentials of a process that wants to create a ptrace relationship, which allows local users to obtain root access by leveraging certain scenarios with a parent-child process relationship, where a parent drops privileges and calls execve (potentially allowing control by an attacker). One contributing factor is an object lifetime issue (which can also cause a panic). Another contributing factor is incorrect marking of a ptrace relationship as privileged, which is exploitable through (for example) Polkit's pkexec helper with PTRACE_TRACEME. NOTE: SELinux deny_ptrace might be a usable workaround in some environments.

It was discovered that the get_starttime() function in data/apport did not properly parse the /proc/pid/stat file from the kernel.

The Linux kernel before 5.1-rc5 allows page->_refcount reference count overflow, with resultant use-after-free issues, if about 140 GiB of RAM exists. This is related to fs/fuse/dev.c, fs/pipe.c, fs/splice.c, include/linux/mm.h, include/linux/pipe_fs_i.h, kernel/trace/trace.c, mm/gup.c, and mm/hugetlb.c. It can occur with FUSE requests.

The VGA module in QEMU improperly performs bounds checking on banked access to video memory, which allows local guest OS administrators to execute arbitrary code on the host by changing access modes after setting the bank register, aka the "Dark Portal" issue.

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).

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.

Integer overflow in the xt_alloc_table_info function in net/netfilter/x_tables.c in the Linux kernel through 4.5.2 on 32-bit platforms allows local users to gain privileges or cause a denial of service (heap memory corruption) via an IPT_SO_SET_REPLACE setsockopt call.

In sk_clone_lock of sock.c, there is a possible memory corruption due to type confusion. This could lead to local escalation of privilege with no additional execution privileges needed. User interaction is not needed for exploitation. Product: Android. Versions: Android kernel. Android ID: A-113509306. References: Upstream kernel.

The do_remount function in fs/namespace.c in the Linux kernel through 3.16.1 does not maintain the MNT_LOCK_READONLY bit across a remount of a bind mount, which allows local users to bypass an intended read-only restriction and defeat certain sandbox protection mechanisms via a "mount -o remount" command within a user namespace.

The vmware-vga driver (hw/display/vmware_vga.c) in QEMU allows local guest users to write to qemu memory locations and gain privileges via unspecified parameters related to rectangle handling.

The udl_fb_mmap function in drivers/gpu/drm/udl/udl_fb.c at the Linux kernel version 3.4 and up to and including 4.15 has an integer-overflow vulnerability allowing local users with access to the udldrmfb driver to obtain full read and write permissions on kernel physical pages, resulting in a code execution in kernel space.

A statement in the System Programming Guide of the Intel 64 and IA-32 Architectures Software Developer's Manual (SDM) was mishandled in the development of some or all operating-system kernels, resulting in unexpected behavior for #DB exceptions that are deferred by MOV SS or POP SS, as demonstrated by (for example) privilege escalation in Windows, macOS, some Xen configurations, or FreeBSD, or a Linux kernel crash. The MOV to SS and POP SS instructions inhibit interrupts (including NMIs), data breakpoints, and single step trap exceptions until the instruction boundary following the next instruction (SDM Vol. 3A; section 6.8.3). (The inhibited data breakpoints are those on memory accessed by the MOV to SS or POP to SS instruction itself.) Note that debug exceptions are not inhibited by the interrupt enable (EFLAGS.IF) system flag (SDM Vol. 3A; section 2.3). If the instruction following the MOV to SS or POP to SS instruction is an instruction like SYSCALL, SYSENTER, INT 3, etc. that transfers control to the operating system at CPL < 3, the debug exception is delivered after the transfer to CPL < 3 is complete. OS kernels may not expect this order of events and may therefore experience unexpected behavior when it occurs.

In nfc_llcp_build_sdreq_tlv of llcp_commands.c, there is a possible out of bounds write due to a missing bounds check. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation. Product: Android. Versions: Android kernel. Android ID: A-73083945.

In the hidp_process_report in bluetooth, there is an integer overflow. This could lead to an out of bounds write with no additional execution privileges needed. User interaction is not needed for exploitation. Product: Android Versions: Android kernel Android ID: A-65853588 References: Upstream kernel.

In hid_debug_events_read of drivers/hid/hid-debug.c, there is a possible out of bounds write due to a missing bounds check. This could lead to local escalation of privilege with System execution privileges needed. User interaction is not needed for exploitation. Product: Android Versions: Android kernel Android ID: A-71361580.

Incorrect buffer length handling in the ncp_read_kernel function in fs/ncpfs/ncplib_kernel.c in the Linux kernel through 4.15.11, and in drivers/staging/ncpfs/ncplib_kernel.c in the Linux kernel 4.16-rc through 4.16-rc6, could be exploited by malicious NCPFS servers to crash the kernel or execute code.

systemd-tmpfiles in systemd through 237 mishandles symlinks present in non-terminal path components, which allows local users to obtain ownership of arbitrary files via vectors involving creation of a directory and a file under that directory, and later replacing that directory with a symlink. This occurs even if the fs.protected_symlinks sysctl is turned on.

The blkcg_init_queue function in block/blk-cgroup.c in the Linux kernel before 4.11 allows local users to cause a denial of service (double free) or possibly have unspecified other impact by triggering a creation failure.

Apport does not properly handle crashes originating from a PID namespace allowing local users to create certain files as root which an attacker could leverage to perform a denial of service via resource exhaustion, possibly gain root privileges, or escape from containers. The is_same_ns() function returns True when /proc/<global pid>/ does not exist in order to indicate that the crash should be handled in the global namespace rather than inside of a container. However, the portion of the data/apport code that decides whether or not to forward a crash to a container does not always replace sys.argv[1] with the value stored in the host_pid variable when /proc/<global pid>/ does not exist which results in the container pid being used in the global namespace. This flaw affects versions 2.20.8-0ubuntu4 through 2.20.9-0ubuntu7, 2.20.7-0ubuntu3.7, 2.20.7-0ubuntu3.8, 2.20.1-0ubuntu2.15 through 2.20.1-0ubuntu2.17, and 2.14.1-0ubuntu3.28.

An issue was discovered in the Linux kernel before 4.19.9. The USB subsystem mishandles size checks during the reading of an extra descriptor, related to __usb_get_extra_descriptor in drivers/usb/core/usb.c.

In the Linux kernel 4.14.x, 4.15.x, 4.16.x, 4.17.x, and 4.18.x before 4.18.13, faulty computation of numeric bounds in the BPF verifier permits out-of-bounds memory accesses because adjust_scalar_min_max_vals in kernel/bpf/verifier.c mishandles 32-bit right shifts.

In the Linux kernel 5.5.0 and newer, the bpf verifier (kernel/bpf/verifier.c) did not properly restrict the register bounds for 32-bit operations, leading to out-of-bounds reads and writes in kernel memory. The vulnerability also affects the Linux 5.4 stable series, starting with v5.4.7, as the introducing commit was backported to that branch. This vulnerability was fixed in 5.6.1, 5.5.14, and 5.4.29. (issue is aka ZDI-CAN-10780)

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.