Linux Linux Kernel

net/can/bcm.c in the Linux kernel through 5.12.10 allows local users to obtain sensitive information from kernel stack memory because parts of a data structure are uninitialized.

Improper access control in BlueZ may allow an authenticated user to potentially enable information disclosure via adjacent access.

A flaw double-free memory corruption in the Linux kernel HCI device initialization subsystem was found in the way user attach malicious HCI TTY Bluetooth device. A local user could use this flaw to crash the system. This flaw affects all the Linux kernel versions starting from 3.13.

An issue was discovered in the Linux kernel before 5.8.2. fs/io_uring.c has a use-after-free related to io_async_task_func and ctx reference holding, aka CID-6d816e088c35.

An issue was discovered in the Linux kernel before 5.8.1. net/bluetooth/hci_event.c has a slab out-of-bounds read in hci_extended_inquiry_result_evt, aka CID-51c19bf3d5cf.

An issue was discovered in the Linux kernel before 5.10. drivers/infiniband/core/ucma.c has a use-after-free because the ctx is reached via the ctx_list in some ucma_migrate_id situations where ucma_close is called, aka CID-f5449e74802c.

An issue was discovered in the Linux kernel before 5.0.19. The XFRM subsystem has a use-after-free, related to an xfrm_state_fini panic, aka CID-dbb2483b2a46.

An issue was discovered in the Linux kernel before 4.14.16. There is a use-after-free in net/sctp/socket.c for a held lock after a peel off, aka CID-a0ff660058b8.

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//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).

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 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).

A flaw was found in the Linux kernel. An index buffer overflow during Direct IO write leading to the NFS client to crash. In some cases, a reach out of the index after one memory allocation by kmalloc will cause a kernel panic. The highest threat from this vulnerability is to data confidentiality and system availability.

There is a flaw reported in the Linux kernel in versions before 5.9 in drivers/gpu/drm/nouveau/nouveau_sgdma.c in nouveau_sgdma_create_ttm in Nouveau DRM subsystem. The issue results from the lack of validating the existence of an object prior to performing operations on the object. An attacker with a local account with a root privilege, can leverage this vulnerability to escalate privileges and execute code in the context of the kernel.

A flaw was found in the Linux kernel in versions before 5.4.92 in the BPF protocol. This flaw allows an attacker with a local account to leak information about kernel internal addresses. The highest threat from this vulnerability is to confidentiality.

kernel/bpf/verifier.c in the Linux kernel through 5.12.7 enforces incorrect limits for pointer arithmetic operations, aka CID-bb01a1bba579. This can be abused to perform out-of-bounds reads and writes in kernel memory, leading to local privilege escalation to root. In particular, there is a corner case where the off reg causes a masking direction change, which then results in an incorrect final aux->alu_limit.

A memory disclosure flaw was found in the Linux kernel's versions before 4.18.0-193.el8 in the sysctl subsystem when reading the /proc/sys/kernel/rh_features file. This flaw allows a local user to read uninitialized values from the kernel memory. The highest threat from this vulnerability is to confidentiality.

Mounting /proc filesystem via chroot command silently mounts it in read-write mode. The user could bypass the chroot environment and gain write access to files, he would never have otherwise.

An issue was discovered in Linux: KVM through Improper handling of VM_IO|VM_PFNMAP vmas in KVM can bypass RO checks and can lead to pages being freed while still accessible by the VMM and guest. This allows users with the ability to start and control a VM to read/write random pages of memory and can result in local privilege escalation.

A flaw was found in the Linux kernel's implementation of string matching within a packet. A privileged user (with root or CAP_NET_ADMIN) when inserting iptables rules could insert a rule which can panic the system. Kernel before kernel 5.5-rc1 is affected.

A flaw was found in the JFS filesystem code in the Linux Kernel which allows a local attacker with the ability to set extended attributes to panic the system, causing memory corruption or escalating privileges. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

A vulnerability was found in Linux kernel where non-blocking socket in llcp_sock_connect() leads to leak and eventually hanging-up the system.

A vulnerability was found in Linux Kernel, where a refcount leak in llcp_sock_connect() causing use-after-free which might lead to privilege escalations.

A vulnerability was found in Linux Kernel where refcount leak in llcp_sock_bind() causing use-after-free which might lead to privilege escalations.

A vulnerability was found in the Linux Kernel where the function sunkbd_reinit having been scheduled by sunkbd_interrupt before sunkbd being freed. Though the dangling pointer is set to NULL in sunkbd_disconnect, there is still an alias in sunkbd_reinit causing Use After Free.

A flaw was found in Linux Kernel because access to the global variable fg_console is not properly synchronized leading to a use after free in con_font_op.