Red Hat Linux Linux Kernel Vulnerabilities & Security Advisories
2148 advisories tracked · Red Hat Security Data API · 1 listed in the CISA Known Exploited Vulnerabilities catalog
Every row below is a published Red Hat Linux advisory that VulniPulse classified as Linux Kernel, with the CVEs, affected and fixed releases and exploitation status the vendor stated. Severity mix: 781 high, 1364 medium, 1 low.
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Latest Red Hat Linux Kernel advisories
Medium [CVE-2026-64403] validate option length before reading conf opt value
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: validate option length before reading conf opt value l2cap_get_conf_opt() derives the option length from the attacker-controlled opt->len field and immediately dereferences opt->val (as u8, get_unaligned_le16() or get_unaligned_le32(), or a raw pointer for the default case) before any caller has confirmed that opt->len bytes are present in the buffer. The callers (l2cap_parse_conf_req(), l2cap_parse_conf_rsp() and l2cap_conf_rfc_get()) only detect a malformed option afterwards, once the running length has gone negative, by which point the out-of-bounds read has already executed. An existing post-hoc length check keeps the garbage value from being consumed, so this is not a data leak in the current control flow. It is still a validate-after-use ordering bug: up to 4 bytes are read past the end of the buffer before it is known to contain them, and it is fragile to future changes in the callers. Fix it at the source. Pass the end of the buffer into l2cap_get_conf_opt() and refuse to touch opt->val unless the full option (header + value) fits. Each caller computes an end pointer once before the loop and checks the return value directly instead of inferring the error from a negative length.
Medium [CVE-2026-64352] Allow LPM map access from sleepable BPF programs
In the Linux kernel, the following vulnerability has been resolved: bpf: Allow LPM map access from sleepable BPF programs trie_lookup_elem() annotates its rcu_dereference_check() walks with only rcu_read_lock_bh_held(). Because rcu_dereference_check(p, c) resolves to "c || rcu_read_lock_held()", this passes for XDP/NAPI and classic RCU readers but fails for sleepable BPF programs, which enter via __bpf_prog_enter_sleepable() and hold only rcu_read_lock_trace(). trie_update_elem() and trie_delete_elem() have the same problem in a different form: they walk the trie with plain rcu_dereference(), which asserts rcu_read_lock_held() unconditionally. Both are reachable from sleepable BPF programs via the bpf_map_update_elem / bpf_map_delete_elem helpers, and from the syscall path under classic rcu_read_lock(). In the writer paths the trie is actually protected by trie->lock (an rqspinlock taken across the walk); we never relied on the RCU read-side lock to keep nodes alive there. A sleepable LSM hook that ends up touching an LPM trie therefore triggers lockdep on debug kernels: ============================= WARNING: suspicious RCU usage 7.1.0-... Tainted: G E ----------------------------- kernel/bpf/lpm_trie.c:249 suspicious rcu_dereference_check() usage!
Medium [CVE-2026-64322] validate sparing table length as an entry count, not a byte count
In the Linux kernel, the following vulnerability has been resolved: udf: validate sparing table length as an entry count, not a byte count udf_load_sparable_map() accepts a sparing table when sizeof(*st) + le16_to_cpu(st->reallocationTableLen) > sb->s_blocksize is false, i.e. it treats reallocationTableLen as a number of BYTES that must fit in the block. But the table is walked as an array of 8-byte sparingEntry elements: for (i = 0; i reallocationTableLen); i++) { struct sparingEntry *entry = &st->mapEntry[i];... entry->origLocation... } in udf_get_pblock_spar15() and udf_relocate_blocks(). A reallocationTableLen of N therefore passes the check whenever sizeof(*st) + N mapEntry[] is an out-of-bounds write. A flaw was found in the Linux kernel's Universal Disk Format (UDF) filesystem. This can lead to memory corruption, potentially resulting in a denial of service or arbitrary code execution. This issue is triggered by a specially crafted disk image containing on-disk metadata inconsistencies. Exploitation requires that an attacker convince a user to download and use a malicious image from an untrusted source, a scenario with limited practical impact. Red Hat rates this as Low severity. Weakness: CWE-125. Affected products named by the advisory: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 7; Red Hat Enterprise Linux 8; and 2 more.
Medium [CVE-2026-64474] prevent infinite loop in vfio_mig_get_next_state on blocked arc
In the Linux kernel, the following vulnerability has been resolved: vfio: prevent infinite loop in vfio_mig_get_next_state() on blocked arc vfio_mig_get_next_state() walks vfio_from_fsm_table[] one step at a time, looping to skip optional states the device does not support until *next_fsm is supported. A blocked transition is encoded as VFIO_DEVICE_STATE_ERROR, which the trailing return reports as -EINVAL. The skip loop does not account for the ERROR sentinel. state_flags_table[ERROR] is ~0U and vfio_from_fsm_table[ERROR][*] is ERROR, so once *next_fsm becomes ERROR the loop condition stays true and *next_fsm never changes. The blocked arcs STOP_COPY -> PRE_COPY and STOP_COPY -> PRE_COPY_P2P map to ERROR yet pass the support check on a precopy-capable device, causing the loop to spin forever while holding the driver state mutex. This can result in a soft lockup, and a panic with softlockup_panic set. A flaw was found in the Linux kernel's Virtual Function I/O (VFIO) device migration feature. The `vfio_mig_get_next_state()` function, responsible for managing device migration states, contains an infinite loop. This occurs when processing certain blocked transitions, causing the system to hold a driver state mutex indefinitely. Red Hat severity: Low — CVSS 5.5 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H). Weakness: CWE-835.
Medium [CVE-2026-64308] ccp - Do not initialize SNP for ioctl(SNP_VLEK_LOAD)
In the Linux kernel, the following vulnerability has been resolved: crypto: ccp - Do not initialize SNP for ioctl(SNP_VLEK_LOAD) Sashiko notes: > if SEV initialization fails and KVM is actively running normal VMs, could a > userspace process trigger this code path via /dev/sev ioctls (e.g., > SEV_PDH_GEN) and zero out MSR_VM_HSAVE_PA globally? Would the next VMRUN > execution for an active VM trigger a general protection fault and crash the > host? The SEV firmware docs for SNP_VLEK_LOAD note: > On SNP_SHUTDOWN, the VLEK is deleted. That is, the initialization/shutdown wrapper here is pointless, because the firmware immediately throws away the key anyway. Instead, refuse to do anything if SNP has not been previously initialized. This is an ABI break: before, this was a no-op and almost certainly a mistake by userspace, and now it returns -ENODEV. ABI compatibility could be maintained here by simply returning 0 in the check instead. A flaw was found in the Linux kernel's crypto: ccp module, which handles AMD Secure Encrypted Virtualization (SEV) and Secure Nested Paging (SNP) features. A local user, by sending specific commands through the /dev/sev interface, could exploit improper initialization handling. If SEV initialization has failed and virtual machines are active, this could lead to a system crash, resulting in a Denial of Service (DoS).
Medium [CVE-2026-64458] handle extreme intervals in damon_hot_score
In the Linux kernel, the following vulnerability has been resolved: mm/damon/ops-common: handle extreme intervals in damon_hot_score() Fix three issues in damon_hot_score() that comes from wrong handling of extreme (zero or too high) monitoring intervals user setup. When the user sets sampling interval zero, damon_max_nr_accesses(), which is called from damon_hot_score(), causes a divide-by-zero. Needless to say, it is a problem. It is wrong, since the real maximum nr_acceses in the setup should be one. Worse yet, it can cause another divide-by-zero from its caller, damon_hot_score(), since it uses damon_max_nr_accesses() return value as a denominator. When the user sets the aggregation interval very high, damon_hot_score() could return a value out of [0, DAMOS_MAX_SCORE] range. Since the return value is used as an index to the regions_score_histogram array, which is DAMOS_MAX_SCORE+1 size, it causes out of bounds array access. The issues can be relatively easily reproduced like below. Affected products named by the advisory: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 9; Red Hat package: kernel-rt.
Medium [CVE-2026-64336] fix information leak
In the Linux kernel, the following vulnerability has been resolved: USB: serial: keyspan_pda: fix information leak The write() callback is supposed to return the number of characters accepted or a negative errno. Since the addition of write fifo support the keyspan_pda implementation will however return the number characters submitted to the device if the write urb is not already in use. If this number is larger than the number of characters passed to write(), the line discipline continues writing data from beyond the tty write buffer. Fix the information leak by making sure that keyspan_pda_write_start() returns zero on success as intended. An issue with the write() callback function allows it to report more data written than was actually provided. This can lead to the system writing data beyond its allocated buffer, resulting in an information leak. A local attacker could exploit this to potentially gain access to sensitive information. Red Hat severity: Moderate — CVSS 5.5 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H). Weakness: CWE-787. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9. Will not fix / out of support: Red Hat Enterprise Linux 6. Red Hat does not currently list a fixing RHSA for this CVE. Affected products named by the advisory: Red Hat package: kernel-rt.
Medium [CVE-2026-64282] Don't leak PFN when kvm_translate_vncr races MMU notifier
In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Don't leak PFN when kvm_translate_vncr() races MMU notifier In the case that kvm_translate_vncr() races with an MMU notifier the early return does not release a reference on the faulted in PFN. Add the necessary call to kvm_release_faultin_page() for the unused PFN. A flaw was found in the Linux kernel's KVM (Kernel-based Virtual Machine) for arm64 architectures. A race condition between the `kvm_translate_vncr()` function and an MMU (Memory Management Unit) notifier can lead to a Page Frame Number (PFN) leak. This occurs because an early return in `kvm_translate_vncr()` fails to release a reference on a faulted-in PFN, potentially leading to resource exhaustion or information disclosure. Red Hat severity: Low — CVSS 5.5 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H). Weakness: CWE-772. Affected Red Hat products: Red Hat Enterprise Linux 10. Red Hat does not currently list a fixing RHSA for this CVE. Affected products named by the advisory: Red Hat package: kernel.
Medium [CVE-2026-64284] Ensure vendor's exit handler runs before fastpath userspace exits
In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Ensure vendor's exit handler runs before fastpath userspace exits Move the handling of fastpath userspace exits into vendor code to ensure KVM runs vendor specific operations that need to run before userspace gains control of the vCPU. E.g. for VMX (and soon to be for SVM as well), KVM needs to flush the PML buffer prior to exiting to userspace, otherwise any memory written by the final KVM_RUN might never be flagged as dirty. Note, waiting to snapshot CR0 and CR3 until svm_handle_exit() is flawed in general, as that risks consuming stale state in a fastpath handler. That will be addressed in a future change. A flaw was found in the Linux kernel's Kernel-based Virtual Machine (KVM) for x86 systems. This vulnerability occurs when KVM handles fastpath exits, where it may fail to execute vendor-specific cleanup operations before returning control to the virtual machine's userspace. Consequently, memory written by the virtual machine might not be correctly flagged as dirty, leading to the consumption of outdated data. A local attacker with access to a virtual machine could potentially exploit this to cause data integrity issues within the virtualized environment. Red Hat severity: Moderate — CVSS 5.5 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H). Weakness: CWE-367.
Medium [CVE-2026-64383] fix double-free in SMB2_flush replay
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix double-free in SMB2_flush() replay SMB2_flush() keeps its response buffer bookkeeping across replay attempts. If a replayable flush response is received and the retry then fails before cifs_send_recv() stores a replacement response, flush_exit will free the stale response pointer a second time. Reinitialize resp_buftype and rsp_iov at the top of the replay loop so cleanup only acts on response state produced by the current attempt. This fixes a double-free without changing replay handling for successful requests. This vulnerability, a double-free error within the `SMB2_flush()` replay mechanism, occurs when the system attempts to free a memory buffer twice. A malicious SMB server could exploit this by sending a specially crafted flush response, potentially leading to memory corruption. This could result in a denial of service or, in some scenarios, arbitrary code execution. Red Hat severity: Important — CVSS 6.4 (CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:L). Weakness: CWE-1341. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 9. Red Hat does not currently list a fixing RHSA for this CVE. Affected products named by the advisory: Red Hat package: kernel-rt.
Medium [CVE-2026-64405] Fix null ptr deref in hci_abort_conn
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_conn: Fix null ptr deref in hci_abort_conn() hci_abort_conn() read hci_skb_event(hdev->sent_cmd) when a connection was pending, but hdev->sent_cmd can be NULL while req_status is still HCI_REQ_PEND, leading to a NULL pointer dereference and a general protection fault from the hci_rx_work() receive path. Instead of inspecting hdev->sent_cmd, track the in-flight create connection command with a new per-connection HCI_CONN_CREATE flag and route all cancellation through hci_cancel_connect_sync(), which dispatches to a dedicated per-type cancel function. The create command is in exactly one of two states: still queued, or in flight. The cancel function holds cmd_sync_work_lock across the whole decision: the worker takes this lock to dequeue every entry, so while it is held a queued command cannot start running and an in-flight command cannot complete and let the next command become pending. This keeps the flag test and hci_cmd_sync_cancel() atomic with respect to the worker, so a queued command is simply dequeued, and an in-flight command owned by this connection is cancelled without the risk of cancelling an unrelated command that became pending in the meantime.
Medium [CVE-2026-64301] fix of_node refcount leak in scmi_regulator_probe
In the Linux kernel, the following vulnerability has been resolved: regulator: scmi: fix of_node refcount leak in scmi_regulator_probe() scmi_regulator_probe() calls of_find_node_by_name() which takes a reference on the returned device node. On the error path where process_scmi_regulator_of_node() fails, the function returns without calling of_node_put() on the child node, leaking the reference. An issue in the `scmi_regulator_probe()` function can lead to a reference count leak. This occurs when an error path is triggered during device node processing, causing a resource to not be properly released. Over time, this unreleased resource could potentially impact system stability or performance. Red Hat severity: Low — CVSS 5.5 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H). Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 9. Red Hat does not currently list a fixing RHSA for this CVE. Affected products named by the advisory: Red Hat package: kernel-rt.
Medium [CVE-2026-64315] caam - use print_hex_dump_devel to guard key hex dumps
In the Linux kernel, the following vulnerability has been resolved: crypto: caam - use print_hex_dump_devel to guard key hex dumps Use print_hex_dump_devel() for dumping sensitive key material in *_setkey() to avoid leaking secrets at runtime when CONFIG_DYNAMIC_DEBUG is enabled. A flaw was found in the Linux kernel's Cryptographic Acceleration and Assurance Module (CAAM) driver. When the kernel's dynamic debugging feature is enabled, an attacker could potentially exploit improper handling of key dumps in cryptographic setup functions, leading to the disclosure of confidential information. Red Hat severity: Moderate — CVSS 5.5 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H). Weakness: CWE-215. Affected Red Hat products: Red Hat Enterprise Linux 10. Red Hat does not currently list a fixing RHSA for this CVE. Affected products named by the advisory: Red Hat package: kernel.
Medium [CVE-2026-64480] check snd_ctl_new1 return value
In the Linux kernel, the following vulnerability has been resolved: ALSA: ice1712: check snd_ctl_new1() return value snd_ctl_new1() can return NULL when memory allocation fails. The ice1712 driver calls snd_ctl_new1() without checking the return value before dereferencing the pointer in multiple places (ice1712.c, ice1724.c, aureon.c), which can lead to NULL pointer dereferences. Add NULL checks after snd_ctl_new1() calls and return -ENOMEM if any fails. A flaw was found in the Linux kernel's Advanced Linux Sound Architecture (ALSA) ice1712 driver. This vulnerability occurs because the `snd_ctl_new1()` function, which allocates memory, can return a null value upon failure, but the driver does not properly check for this. An attacker could potentially trigger a memory allocation failure, leading to a null pointer dereference and causing the system to crash, resulting in a Denial of Service (DoS). Red Hat severity: Low — CVSS 5.5 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H). Weakness: CWE-476. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9. Will not fix / out of support: Red Hat Enterprise Linux 6. Red Hat does not currently list a fixing RHSA for this CVE. Affected products named by the advisory: Red Hat package: kernel-rt.
Medium [CVE-2026-64291] Set veventq_depth upper bound
In the Linux kernel, the following vulnerability has been resolved: iommufd: Set veventq_depth upper bound iommufd_veventq_alloc() accepts any!0 veventq_depth from userspace, with an upper bound at U32_MAX. This leaves a vulnerability where userspace can allocate excessively large queues to exhaust kernel memory reserves. Cap the veventq_depth (maximum number of entries) to 1 << 19, matching the maximum number of entries in the SMMUv3 EVTQ (the largest use case today). A local user could exploit this vulnerability by allocating excessively large event queues, leading to the exhaustion of kernel memory. This can result in a Denial of Service (DoS) for the system. Red Hat severity: Low — CVSS 5.5 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H). Weakness: CWE-770. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 9. Red Hat does not currently list a fixing RHSA for this CVE. Affected products named by the advisory: Red Hat package: kernel-rt.
Medium [CVE-2026-64486] check snd_ctl_new1 return value
In the Linux kernel, the following vulnerability has been resolved: ALSA: cmipci: check snd_ctl_new1() return value snd_ctl_new1() can return NULL when memory allocation fails. snd_cmipci_spdif_controls() does not check the return value before dereferencing kctl->id.device, which can lead to a NULL pointer dereference. Add NULL checks after snd_ctl_new1() calls and return -ENOMEM if any fails. A flaw was found in the Linux kernel's Advanced Linux Sound Architecture (ALSA) cmipci component. A local attacker could exploit this to trigger a null pointer dereference, leading to a system crash and a denial of service (DoS). Red Hat severity: Low — CVSS 5.5 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H). Weakness: CWE-476. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9. Will not fix / out of support: Red Hat Enterprise Linux 6. Red Hat does not currently list a fixing RHSA for this CVE. Affected products named by the advisory: Red Hat package: kernel-rt.
Medium [CVE-2026-64279] fix adapter deregistration race
In the Linux kernel, the following vulnerability has been resolved: i2c: core: fix adapter deregistration race Adapters can be looked up by their id using i2c_get_adapter() which takes a reference to the embedded struct device. Remove the adapter from the IDR before tearing it down during deregistration (and on registration failure) to make sure its resources are not accessed after having been freed (e.g. the device name). A flaw was found in the Linux kernel, specifically within its I2C (Inter-Integrated Circuit) core component. This vulnerability involves a race condition that occurs when an I2C adapter is being removed from the system. During this process, it is possible for the system to attempt to access the adapter's memory after it has already been released. A local attacker could potentially exploit this issue, leading to system instability, unauthorized information access, or the execution of malicious code. Red Hat severity: Moderate — CVSS 5.5 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H). Weakness: CWE-367. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9. Will not fix / out of support: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 8; Red Hat Enterprise Linux 9. Red Hat does not currently list a fixing RHSA for this CVE. Affected products named by the advisory: Red Hat package: kernel-rt.
Medium [CVE-2026-64330] Validate SVID index in svdm_consume_modes
In the Linux kernel, the following vulnerability has been resolved: usb: typec: tcpm: Validate SVID index in svdm_consume_modes() In svdm_consume_modes(), the SVID value is read from pmdata->svids using pmdata->svid_index as an array index without bounds validation: paltmode->svid = pmdata->svids[pmdata->svid_index]; If pmdata->svid_index is driven beyond SVID_DISCOVERY_MAX (16), it results in an out-of-bounds read of the pmdata->svids array. Because pd_mode_data is embedded inside struct tcpm_port, indexing past svids reads into adjacent fields. In particular: - At index 16, it reads the altmodes count. - At index 18 and beyond, it reads into altmode_desc[], which contains partner-supplied SVDM Discovery Modes VDOs. By injecting a chosen SVID into altmode_desc[0].vdo and driving svid_index to 20, the partner can force paltmode->svid to be loaded with an arbitrary, partner- chosen SVID, which is then registered via typec_partner_register_altmode(). Fix this by validating that pmdata->svid_index is non-negative and strictly less than pmdata->nsvids before accessing the pmdata->svids array inside svdm_consume_modes(). A malicious USB-C partner device could exploit an out-of-bounds read vulnerability in the `svdm_consume_modes()` function. By manipulating the SVID (Standard or Vendor ID) index, the partner device can force the system to register an arbitrary SVID.
Medium [CVE-2026-64529] qat - remove unused character device and IOCTLs
In the Linux kernel, the following vulnerability has been resolved: crypto: qat - remove unused character device and IOCTLs The QAT driver exposes a character device (qat_adf_ctl) with IOCTLs for device configuration, start, stop, status query and enumeration. These IOCTLs are not part of any public uAPI header and have no known in-tree or out-of-tree users. Device lifecycle is already managed via sysfs. The ioctl interface also increases the attack surface and is the subject of a number of bug reports. Remove the character device, the IOCTL definitions, and the related data structures (adf_dev_status_info, adf_user_cfg_key_val, adf_user_cfg_section, adf_user_cfg_ctl_data). Drop the now-unused adf_cfg_user.h header and strip adf_ctl_drv.c down to the minimal module_init/module_exit hooks for workqueue, AER, and crypto/compression algorithm registration. Clean up leftover dead code that was only reachable from the removed IOCTL paths: adf_cfg_del_all(), adf_devmgr_verify_id(), adf_devmgr_get_num_dev(), adf_devmgr_get_dev_by_id(), adf_get_vf_real_id() and the unused ADF_CFG macros. Additionally, drop the entry associated to QAT IOCTLs in ioctl-number.rst. Unused character devices and IOCTLs (Input/Output Control) were exposed, which increased the potential attack surface.
Medium [CVE-2026-64522] Fix eswitch mode block underflow on IPsec acquire SA
In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix eswitch mode block underflow on IPsec acquire SA mlx5e_xfrm_add_state() handles acquire-flow temporary SAs by allocating software state and skipping hardware offload setup. That path jumps to the common success label before taking the eswitch mode block. After tunnel-mode validation was moved earlier, the common success label unconditionally calls mlx5_eswitch_unblock_mode(). For acquire SAs, this decrements esw->offloads.num_block_mode without a matching increment. Return directly after installing the acquire SA offload handle, so only the paths that successfully called mlx5_eswitch_block_mode() call the matching unblock. A flaw was found in the Linux kernel's mlx5e network driver. When handling temporary Security Associations (SAs) for IPsec, the `mlx5e_xfrm_add_state()` function incorrectly decrements a counter without a corresponding increment. This underflow in the eswitch mode block mechanism can lead to a denial of service, potentially disrupting network operations. Red Hat severity: Low — CVSS 5.5 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H). Weakness: CWE-191. Affected Red Hat products: Red Hat Enterprise Linux 10; Red Hat Enterprise Linux 6; Red Hat Enterprise Linux 9. Will not fix / out of support: Red Hat Enterprise Linux 6.