Linux Kernel up to 7.2-rc2 Audit Queue audit_log_start race condition

CVSS Meta Temp Score
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CTI Interest Score
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9.5$0-$5k0.80

Summaryinfo

A vulnerability labeled as very critical has been found in Linux Kernel up to 7.2-rc2. This vulnerability affects the function audit_log_start of the component Audit Queue. The manipulation results in race condition. This vulnerability is reported as CVE-2026-64435. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability, which was classified as very critical, was found in Linux Kernel up to 7.2-rc2. Affected is the function audit_log_start of the component Audit Queue. The manipulation with an unknown input leads to a race condition vulnerability. CWE is classifying the issue as CWE-362. The product contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

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]

The advisory is shared for download at git.kernel.org. This vulnerability is traded as CVE-2026-64435 since 07/19/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 07/25/2026).

Upgrading to version 5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.96, 6.18.39, 7.1.4 or 7.2-rc3 eliminates this vulnerability. Applying the patch 69f98fff30bdaa72b0cb0e7e078ab6456a0a59b0/b35597bdae1a5d8395da4b9baa993b9b71f74d68/e575dabb805252e3113fdc3f56f6ecacfde422d0/7ff42312ccde549f8c698723822c7db35107a39b/a3d85dec60bb0622360fc176b2a51abdbe2ff0ad/fe997a84a385f840b593ead92e575503a5046cee/c5186201fa7030289cc4fe23fae87a3fcb566856/c9a71daaecb2fb1d8c704545cc0b1c920b9bf5d7 is able to eliminate this problem.

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Productinfo

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.5

VulDB Base Score: 9.9
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Race condition
CWE: CWE-362
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 5.10.261/5.15.212/6.1.178/6.6.145/6.12.96/6.18.39/7.1.4/7.2-rc3
Patch: 69f98fff30bdaa72b0cb0e7e078ab6456a0a59b0/b35597bdae1a5d8395da4b9baa993b9b71f74d68/e575dabb805252e3113fdc3f56f6ecacfde422d0/7ff42312ccde549f8c698723822c7db35107a39b/a3d85dec60bb0622360fc176b2a51abdbe2ff0ad/fe997a84a385f840b593ead92e575503a5046cee/c5186201fa7030289cc4fe23fae87a3fcb566856/c9a71daaecb2fb1d8c704545cc0b1c920b9bf5d7

Timelineinfo

07/19/2026 CVE reserved
07/25/2026 +6 days Advisory disclosed
07/25/2026 +0 days VulDB entry created
07/25/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-64435 (🔒)
GCVE (CVE): GCVE-0-2026-64435
GCVE (VulDB): GCVE-100-383232

Entryinfo

Created: 07/25/2026 18:43
Changes: 07/25/2026 18:43 (59)
Complete: 🔍
Cache ID: 216::103

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