Linux vulnerabilities

A flaw was found in the blkgs destruction path in block/blk-cgroup.c in the Linux kernel, leading to a cgroup blkio memory leakage problem. When a cgroup is being destroyed, cgroup_rstat_flush() is only called at css_release_work_fn(), which is called when the blkcg reference count reaches 0. This circular dependency will prevent blkcg and some blkgs from being freed after they are made offline. This issue may allow an attacker with a local access to cause system instability, such as an out of memory error.

A vulnerability was found in vhost_new_msg in drivers/vhost/vhost.c in the Linux kernel, which does not properly initialize memory in messages passed between virtual guests and the host operating system in the vhost/vhost.c:vhost_new_msg() function. This issue can allow local privileged users to read some kernel memory contents when reading from the /dev/vhost-net device file.

io_uring UAF, Unix SCM garbage collection

It was discovered that the cls_route filter implementation in the Linux kernel would not remove an old filter from the hashtable before freeing it if its handle had the value 0.

It was discovered that a nft object or expression could reference a nft set on a different nft table, leading to a use-after-free once that table was deleted.

Closing of an event channel in the Linux kernel can result in a deadlock. This happens when the close is being performed in parallel to an unrelated Xen console action and the handling of a Xen console interrupt in an unprivileged guest. The closing of an event channel is e.g. triggered by removal of a paravirtual device on the other side. As this action will cause console messages to be issued on the other side quite often, the chance of triggering the deadlock is not neglectable. Note that 32-bit Arm-guests are not affected, as the 32-bit Linux kernel on Arm doesn't use queued-RW-locks, which are required to trigger the issue (on Arm32 a waiting writer doesn't block further readers to get the lock).

A flaw was found in the ATA over Ethernet (AoE) driver in the Linux kernel. The aoecmd_cfg_pkts() function improperly updates the refcnt on `struct net_device`, and a use-after-free can be triggered by racing between the free on the struct and the access through the `skbtxq` global queue. This could lead to a denial of service condition or potential code execution.

A use-after-free flaw was found in the netfilter subsystem of the Linux kernel. If the catchall element is garbage-collected when the pipapo set is removed, the element can be deactivated twice. This can cause a use-after-free issue on an NFT_CHAIN object or NFT_OBJECT object, allowing a local unprivileged user with CAP_NET_ADMIN capability to escalate their privileges on the system.

A race condition was found in the GSM 0710 tty multiplexor in the Linux kernel. This issue occurs when two threads execute the GSMIOC_SETCONF ioctl on the same tty file descriptor with the gsm line discipline enabled, and can lead to a use-after-free problem on a struct gsm_dlci while restarting the gsm mux. This could allow a local unprivileged user to escalate their privileges on the system.

A use-after-free vulnerability in the Linux kernel's ipv4: igmp component can be exploited to achieve local privilege escalation. A race condition can be exploited to cause a timer be mistakenly registered on a RCU read locked object which is freed by another thread. We recommend upgrading past commit e2b706c691905fe78468c361aaabc719d0a496f1.

A heap out-of-bounds write vulnerability in the Linux kernel's Performance Events system component can be exploited to achieve local privilege escalation. A perf_event's read_size can overflow, leading to an heap out-of-bounds increment or write in perf_read_group(). We recommend upgrading past commit 382c27f4ed28f803b1f1473ac2d8db0afc795a1b.

A use-after-free vulnerability in the Linux kernel's netfilter: nf_tables component can be exploited to achieve local privilege escalation. The function nft_pipapo_walk did not skip inactive elements during set walk which could lead double deactivations of PIPAPO (Pile Packet Policies) elements, leading to use-after-free. We recommend upgrading past commit 317eb9685095678f2c9f5a8189de698c5354316a.

sec_attest_info in drivers/accel/habanalabs/common/habanalabs_ioctl.c in the Linux kernel through 6.6.5 allows an information leak to user space because info->pad0 is not initialized.

An out-of-bounds read vulnerability was found in smb2_dump_detail in fs/smb/client/smb2ops.c in the Linux Kernel. This issue could allow a local attacker to crash the system or leak internal kernel information.

An out-of-bounds read vulnerability was found in smbCalcSize in fs/smb/client/netmisc.c in the Linux Kernel. This issue could allow a local attacker to crash the system or leak internal kernel information.

A race condition was found in the QXL driver in the Linux kernel. The qxl_mode_dumb_create() function dereferences the qobj returned by the qxl_gem_object_create_with_handle(), but the handle is the only one holding a reference to it. This flaw allows an attacker to guess the returned handle value and trigger a use-after-free issue, potentially leading to a denial of service or privilege escalation.

A flaw was found in KVM. An improper check in svm_set_x2apic_msr_interception() may allow direct access to host x2apic msrs when the guest resets its apic, potentially leading to a denial of service condition.

The brcm80211 component in the Linux kernel through 6.5.10 has a brcmf_cfg80211_detach use-after-free in the device unplugging (disconnect the USB by hotplug) code. For physically proximate attackers with local access, this "could be exploited in a real world scenario." This is related to brcmf_cfg80211_escan_timeout_worker in drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c.

A use-after-free vulnerability was found in drivers/nvme/target/tcp.c` in `nvmet_tcp_free_crypto` due to a logical bug in the NVMe/TCP subsystem in the Linux kernel. This issue may allow a malicious user to cause a use-after-free and double-free problem, which may permit remote code execution or lead to local privilege escalation.

An issue was discovered in the Linux kernel through 6.5.9. During a race with SQ thread exit, an io_uring/fdinfo.c io_uring_show_fdinfo NULL pointer dereference can occur.

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.

A heap out-of-bounds write vulnerability in the Linux kernel's Linux Kernel Performance Events (perf) component can be exploited to achieve local privilege escalation. If perf_read_group() is called while an event's sibling_list is smaller than its child's sibling_list, it can increment or write to memory locations outside of the allocated buffer. We recommend upgrading past commit 32671e3799ca2e4590773fd0e63aaa4229e50c06.

The reference count changes made as part of the CVE-2023-33951 and CVE-2023-33952 fixes exposed a use-after-free flaw in the way memory objects were handled when they were being used to store a surface. When running inside a VMware guest with 3D acceleration enabled, a local, unprivileged user could potentially use this flaw to escalate their privileges.

The Linux kernel before 6.5.4 has an es1 use-after-free in fs/ext4/extents_status.c, related to ext4_es_insert_extent.

An issue was discovered in drivers/net/ethernet/intel/igb/igb_main.c in the IGB driver in the Linux kernel before 6.5.3. A buffer size may not be adequate for frames larger than the MTU.

An issue was discovered in lib/kobject.c in the Linux kernel before 6.2.3. With root access, an attacker can trigger a race condition that results in a fill_kobj_path out-of-bounds write.

A flaw was found in the XFRM subsystem in the Linux kernel. The specific flaw exists within the processing of state filters, which can result in a read past the end of an allocated buffer. This flaw allows a local privileged (CAP_NET_ADMIN) attacker to trigger an out-of-bounds read, potentially leading to an information disclosure.

A flaw was found in the Netfilter subsystem in the Linux kernel. The sctp_mt_check did not validate the flag_count field. This flaw allows a local privileged (CAP_NET_ADMIN) attacker to trigger an out-of-bounds read, leading to a crash or information disclosure.

A flaw was found in the Netfilter subsystem in the Linux kernel. The xt_u32 module did not validate the fields in the xt_u32 structure. This flaw allows a local privileged attacker to trigger an out-of-bounds read by setting the size fields with a value beyond the array boundaries, leading to a crash or information disclosure.

A flaw was found in the Netfilter subsystem in the Linux kernel. The nfnl_osf_add_callback function did not validate the user mode controlled opt_num field. This flaw allows a local privileged (CAP_NET_ADMIN) attacker to trigger an out-of-bounds read, leading to a crash or information disclosure.

A flaw was found in the IPv4 Resource Reservation Protocol (RSVP) classifier in the Linux kernel. The xprt pointer may go beyond the linear part of the skb, leading to an out-of-bounds read in the `rsvp_classify` function. This issue may allow a local user to crash the system and cause a denial of service.

A NULL pointer dereference flaw was found in the Linux kernel ipv4 stack. The socket buffer (skb) was assumed to be associated with a device before calling __ip_options_compile, which is not always the case if the skb is re-routed by ipvs. This issue may allow a local user with CAP_NET_ADMIN privileges to crash the system.

A use-after-free vulnerability in the Linux kernel's netfilter: nf_tables component can be exploited to achieve local privilege escalation. Addition and removal of rules from chain bindings within the same transaction causes leads to use-after-free. We recommend upgrading past commit f15f29fd4779be8a418b66e9d52979bb6d6c2325.

An array indexing vulnerability was found in the netfilter subsystem of the Linux kernel. A missing macro could lead to a miscalculation of the `h->nets` array offset, providing attackers with the primitive to arbitrarily increment/decrement a memory buffer out-of-bound. This issue may allow a local user to crash the system or potentially escalate their privileges on the system.

The fix for XSA-423 added logic to Linux'es netback driver to deal with a frontend splitting a packet in a way such that not all of the headers would come in one piece. Unfortunately the logic introduced there didn't account for the extreme case of the entire packet being split into as many pieces as permitted by the protocol, yet still being smaller than the area that's specially dealt with to keep all (possible) headers together. Such an unusual packet would therefore trigger a buffer overrun in the driver.

A use-after-free vulnerability in the Linux kernel's net/sched: sch_qfq component can be exploited to achieve local privilege escalation. When the plug qdisc is used as a class of the qfq qdisc, sending network packets triggers use-after-free in qfq_dequeue() due to the incorrect .peek handler of sch_plug and lack of error checking in agg_dequeue(). We recommend upgrading past commit 8fc134fee27f2263988ae38920bc03da416b03d8.

A use-after-free vulnerability in the Linux kernel's net/sched: sch_hfsc (HFSC qdisc traffic control) component can be exploited to achieve local privilege escalation. If a class with a link-sharing curve (i.e. with the HFSC_FSC flag set) has a parent without a link-sharing curve, then init_vf() will call vttree_insert() on the parent, but vttree_remove() will be skipped in update_vf(). This leaves a dangling pointer that can cause a use-after-free. We recommend upgrading past commit b3d26c5702c7d6c45456326e56d2ccf3f103e60f.

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 (or backported equivalents).

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.

A use-after-free vulnerability in the Linux kernel's netfilter: nf_tables component can be exploited to achieve local privilege escalation. On an error when building a nftables rule, deactivating immediate expressions in nft_immediate_deactivate() can lead unbinding the chain and objects be deactivated but later used. We recommend upgrading past commit 0a771f7b266b02d262900c75f1e175c7fe76fec2.

A use-after-free vulnerability in the Linux kernel's netfilter: nf_tables component can be exploited to achieve local privilege escalation. When nf_tables_delrule() is flushing table rules, it is not checked whether the chain is bound and the chain's owner rule can also release the objects in certain circumstances. We recommend upgrading past commit 6eaf41e87a223ae6f8e7a28d6e78384ad7e407f8.

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 NULL pointer dereference flaw was found in vmxnet3_rq_cleanup in drivers/net/vmxnet3/vmxnet3_drv.c in the networking sub-component in vmxnet3 in the Linux Kernel. This issue may allow a local attacker with normal user privilege to cause a denial of service due to a missing sanity check during cleanup.

An issue was discovered in l2cap_sock_release in net/bluetooth/l2cap_sock.c in the Linux kernel before 6.4.10. There is a use-after-free because the children of an sk are mishandled.

A flaw was found in the exFAT driver of the Linux kernel. The vulnerability exists in the implementation of the file name reconstruction function, which is responsible for reading file name entries from a directory index and merging file name parts belonging to one file into a single long file name. Since the file name characters are copied into a stack variable, a local privileged attacker could use this flaw to overflow the kernel stack.

A flaw was found in the Linux kernel's TUN/TAP functionality. This issue could allow a local user to bypass network filters and gain unauthorized access to some resources. The original patches fixing CVE-2023-1076 are incorrect or incomplete. The problem is that the following upstream commits - a096ccca6e50 ("tun: tun_chr_open(): correctly initialize socket uid"), - 66b2c338adce ("tap: tap_open(): correctly initialize socket uid"), pass "inode->i_uid" to sock_init_data_uid() as the last parameter and that turns out to not be accurate.

A use-after-free flaw was found in the Linux kernel's netfilter in the way a user triggers the nft_pipapo_remove function with the element, without a NFT_SET_EXT_KEY_END. This issue could allow a local user to crash the system or potentially escalate their privileges on the system.

A flaw was found in the Linux kernel’s IP framework for transforming packets (XFRM subsystem). This issue may allow a malicious user with CAP_NET_ADMIN privileges to cause a 4 byte out-of-bounds read of XFRMA_MTIMER_THRESH when parsing netlink attributes, leading to potential leakage of sensitive heap data to userspace.

A flaw was found in the Linux kernel’s IP framework for transforming packets (XFRM subsystem). This issue may allow a malicious user with CAP_NET_ADMIN privileges to directly dereference a NULL pointer in xfrm_update_ae_params(), leading to a possible kernel crash and denial of service.

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.