CVE-2026-64435audit: Fix data races of skb_queue_len() readers on audit_queue
- 8.2HighCVSS base score
- 0.33%Exploitation in 30 daysEPSS · top 73% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: audit: Fix data races of skb_queue_len() readers on audit_queue Multiple readers access audit_queue.qlen via skb_queue_len() without holding the queue lock or using READ_ONCE(), while kauditd writes to this field via the skb_dequeue() → __skb_unlink() path with WRITE_ONCE() protected by a spinlock. This constitutes data races. All affected skb_queue_len(&audit_queue) call sites: - kauditd_thread() wait_event_freezable() condition - audit_receive_msg() AUDIT_GET handler (s.backlog assignment) - audit_receive() backlog check - audit_log_start() backlog check and pr_warn() KCSAN reports the following conflicting access pattern (one example): ================================================================== BUG: KCSAN: data-race in audit_log_start / skb_dequeue write (marked) to 0xffffffff8512ee20 of 4 bytes by task 661 on cpu 57: skb_dequeue+0x70/0xf0 kauditd_send_queue+0x71/0x220 kauditd_thread+0x1cb/0x430 kthread+0x1c2/0x210 ret_from_fork+0x162/0x1a0 ret_from_fork_asm+0x1a/0x30 read to 0xffffffff8512ee20 of 4 bytes by task 36586 on cpu 1: audit_log_start+0x2a0/0x6b0 audit_core_dumps+0x64/0xa0 do_coredump+0x14b/0x1260 get_signal+0xeb2/0xf70 arch_do_signal_or_restart+0x41/0x170 exit_to_user_mode_loop+0xa2/0x1c0 do_syscall_64+0x1a3/0x1c0 entry_SYSCALL_64_after_hwframe+0x76/0xe0 value changed: 0x00000001 -> 0x00000000 ================================================================== Resolve the race by switching to lockless helper skb_queue_len_lockless(), which internally uses READ_ONCE() and properly pairs with the WRITE_ONCE() write accesses already present on the writer side. [PM: line length tweak]
Timeline
ID reserved
By Linux
- 6 days later
· 6 days later
Published
- 3 months later
· 3 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High8.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H |
| NVDNVD · Modified | 3.1 | High8.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H |
- EPSS (exploitation in 30 days)
- 0.33% · top 73% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.2.
Affected products
- affected 3197542482df22c2a131d4a813280bd7c54cedf5 – < 69f98fff30bdaa72b0cb0e7e078ab6456a0a59b0
- affected 3197542482df22c2a131d4a813280bd7c54cedf5 – < b35597bdae1a5d8395da4b9baa993b9b71f74d68
- affected 3197542482df22c2a131d4a813280bd7c54cedf5 – < e575dabb805252e3113fdc3f56f6ecacfde422d0
- affected 3197542482df22c2a131d4a813280bd7c54cedf5 – < 7ff42312ccde549f8c698723822c7db35107a39b
- affected 3197542482df22c2a131d4a813280bd7c54cedf5 – < a3d85dec60bb0622360fc176b2a51abdbe2ff0ad
- affected 3197542482df22c2a131d4a813280bd7c54cedf5 – < fe997a84a385f840b593ead92e575503a5046cee
- affected 3197542482df22c2a131d4a813280bd7c54cedf5 – < c5186201fa7030289cc4fe23fae87a3fcb566856
- affected 3197542482df22c2a131d4a813280bd7c54cedf5 – < c9a71daaecb2fb1d8c704545cc0b1c920b9bf5d7
- affected 4.10
- unaffected < 4.10
- unaffected 5.10.261 – ≤ 5.10.*
- unaffected 5.15.212 – ≤ 5.15.*
- unaffected 6.1.178 – ≤ 6.1.*
- unaffected 6.6.145 – ≤ 6.6.*
- unaffected 6.12.96 – ≤ 6.12.*
- unaffected 6.18.39 – ≤ 6.18.*
- unaffected 7.1.4 – ≤ 7.1.*
- unaffected 7.2 – ≤ *
References
References8
- https://git.kernel.org/stable/c/69f98fff30bdaa72b0cb0e7e078ab6456a0a59b0 (opens in a new tab)
- https://git.kernel.org/stable/c/b35597bdae1a5d8395da4b9baa993b9b71f74d68 (opens in a new tab)
- https://git.kernel.org/stable/c/e575dabb805252e3113fdc3f56f6ecacfde422d0 (opens in a new tab)
- https://git.kernel.org/stable/c/7ff42312ccde549f8c698723822c7db35107a39b (opens in a new tab)
- https://git.kernel.org/stable/c/a3d85dec60bb0622360fc176b2a51abdbe2ff0ad (opens in a new tab)
- https://git.kernel.org/stable/c/fe997a84a385f840b593ead92e575503a5046cee (opens in a new tab)
- https://git.kernel.org/stable/c/c5186201fa7030289cc4fe23fae87a3fcb566856 (opens in a new tab)
- https://git.kernel.org/stable/c/c9a71daaecb2fb1d8c704545cc0b1c920b9bf5d7 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-48779 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-64435)Record last updated .