Linux Linux Kernel 3.12.4

A use after free flaw was found in hfsplus_put_super in fs/hfsplus/super.c in the Linux Kernel. This flaw could allow a local user to cause a denial of service problem.

A flaw was found in the fixed buffer registration code for io_uring (io_sqe_buffer_register in io_uring/rsrc.c) in the Linux kernel that allows out-of-bounds access to physical memory beyond the end of the buffer. This flaw enables full local privilege escalation.

** DISPUTED ** An issue was discovered in the Linux kernel before 6.3.3. There is an out-of-bounds read in crc16 in lib/crc16.c when called from fs/ext4/super.c because ext4_group_desc_csum does not properly check an offset. NOTE: this is disputed by third parties because the kernel is not intended to defend against attackers with the stated "When modifying the block device while it is mounted by the filesystem" access.

An issue was discovered in the Linux kernel before 6.2. The ntfs3 subsystem does not properly check for correctness during disk reads, leading to an out-of-bounds read in ntfs_set_ea in fs/ntfs3/xattr.c.

A vulnerability was found in the HCI sockets implementation due to a missing capability check in net/bluetooth/hci_sock.c in the Linux Kernel. This flaw allows an attacker to unauthorized execution of management commands, compromising the confidentiality, integrity, and availability of Bluetooth communication.

Copy_from_user on 64-bit versions of the Linux kernel does not implement the __uaccess_begin_nospec allowing a user to bypass the "access_ok" check and pass a kernel pointer to copy_from_user(). This would allow an attacker to leak information. We recommend upgrading beyond commit 74e19ef0ff8061ef55957c3abd71614ef0f42f47

An issue was discovered in the Linux kernel before 6.2.9. A use-after-free was found in bq24190_remove in drivers/power/supply/bq24190_charger.c. It could allow a local attacker to crash the system due to a race condition.

An issue was discovered in netfilter in the Linux kernel before 5.10. There can be a use-after-free in the packet processing context, because the per-CPU sequence count is mishandled during concurrent iptables rules replacement. This could be exploited with the CAP_NET_ADMIN capability in an unprivileged namespace. NOTE: cc00bca was reverted in 5.12.

The Linux kernel before 6.2.9 has a race condition and resultant use-after-free in drivers/net/ethernet/qualcomm/emac/emac.c if a physically proximate attacker unplugs an emac based device.

A use-after-free flaw was found in reconn_set_ipaddr_from_hostname in fs/cifs/connect.c in the Linux kernel. The issue occurs when it forgets to set the free pointer server->hostname to NULL, leading to an invalid pointer request.

A use-after-free flaw was found in xen_9pfs_front_removet in net/9p/trans_xen.c in Xen transport for 9pfs in the Linux Kernel. This flaw could allow a local attacker to crash the system due to a race problem, possibly leading to a kernel information leak.

An out-of-bounds memory access flaw was found in the Linux kernel’s XFS file system in how a user restores an XFS image after failure (with a dirty log journal). This flaw allows a local user to crash or potentially escalate their privileges on the system.

In the Linux kernel through 6.3.1, a use-after-free in Netfilter nf_tables when processing batch requests can be abused to perform arbitrary read and write operations on kernel memory. Unprivileged local users can obtain root privileges. This occurs because anonymous sets are mishandled.

A use-after-free vulnerability was found in the Linux kernel's ext4 filesystem in the way it handled the extra inode size for extended attributes. This flaw could allow a privileged local user to cause a system crash or other undefined behaviors.

An issue was discovered in the Linux kernel before 6.1.11. In net/netrom/af_netrom.c, there is a use-after-free because accept is also allowed for a successfully connected AF_NETROM socket. However, in order for an attacker to exploit this, the system must have netrom routing configured or the attacker must have the CAP_NET_ADMIN capability.

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.

A use-after-free vulnerability in the Linux Kernel Performance Events system can be exploited to achieve local privilege escalation.

The perf_group_detach function did not check the event's siblings' attach_state before calling add_event_to_groups(), but remove_on_exec made it possible to call list_del_event() on before detaching from their group, making it possible to use a dangling pointer causing a use-after-free vulnerability.

We recommend upgrading past commit fd0815f632c24878e325821943edccc7fde947a2.

qfq_change_class in net/sched/sch_qfq.c in the Linux kernel before 6.2.13 allows an out-of-bounds write because lmax can exceed QFQ_MIN_LMAX.

A speculative pointer dereference problem exists in the Linux Kernel on the do_prlimit() function. The resource argument value is controlled and is used in pointer arithmetic for the 'rlim' variable and can be used to leak the contents. We recommend upgrading past version 6.1.8 or commit 739790605705ddcf18f21782b9c99ad7d53a8c11

The current implementation of the prctl syscall does not issue an IBPB immediately during the syscall. The ib_prctl_set  function updates the Thread Information Flags (TIFs) for the task and updates the SPEC_CTRL MSR on the function __speculation_ctrl_update, but the IBPB is only issued on the next schedule, when the TIF bits are checked. This leaves the victim vulnerable to values already injected on the BTB, prior to the prctl syscall.  The patch that added the support for the conditional mitigation via prctl (ib_prctl_set) dates back to the kernel 4.9.176.

We recommend upgrading past commit a664ec9158eeddd75121d39c9a0758016097fa96

A flaw was found in the Linux kernel's netdevsim device driver, within the scheduling of events. This issue results from the improper management of a reference count. This may allow an attacker to create a denial of service condition on the system.

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.

A race condition was found in the Linux kernel's RxRPC network protocol, within the processing of RxRPC bundles. This issue results from the lack of proper locking when performing operations on an object. This may allow an attacker to escalate privileges and execute arbitrary code in the context of the kernel.

The Linux kernel allows userspace processes to enable mitigations by calling prctl with PR_SET_SPECULATION_CTRL which disables the speculation feature as well as by using seccomp. We had noticed that on VMs of at least one major cloud provider, the kernel still left the victim process exposed to attacks in some cases even after enabling the spectre-BTI mitigation with prctl. The same behavior can be observed on a bare-metal machine when forcing the mitigation to IBRS on boot command line.

This happened because when plain IBRS was enabled (not enhanced IBRS), the kernel had some logic that determined that STIBP was not needed. The IBRS bit implicitly protects against cross-thread branch target injection. However, with legacy IBRS, the IBRS bit was cleared on returning to userspace, due to performance reasons, which disabled the implicit STIBP and left userspace threads vulnerable to cross-thread branch target injection against which STIBP protects.

An out-of-bounds write vulnerability was found in the Linux kernel's SLIMpro I2C device driver. The userspace "data->block[0]" variable was not capped to a number between 0-255 and was used as the size of a memcpy, possibly writing beyond the end of dma_buffer. This flaw could allow a local privileged user to crash the system or potentially achieve code execution.