CVE-2026-64518: Linux kernel · tcp: Fix out-of-bounds access for twsk in tcp_ao_established_key().
Affects Linux kernelSource GCVE Database
Not known to be exploited · fixed in 6.12.5 : update Linux kernel when convenient.
Data as of 3 Nov 2026, 18:43 UTC
Rated Medium by Threat Radar's AI analysis · No CVSS score from NVD or the CNA
Thin evidence
One scorer or none- Patch
- Available – fixed in 6.12.5
Exploitation evidence
Disclosed: evidence found.
CVE published 25 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 3 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Linux Linux | Affected
| Fixed in– |
AI-suggested
A fix is available in Linux kernel version 6.12.5, which removes the improper use of lockdep_sock_is_held() for TCP_TIME_WAIT sockets. Users and administrators should update to this or a later kernel version to remediate the vulnerability.
Description
A vulnerability in the Linux kernel's TCP implementation was fixed to prevent out-of-bounds access related to the twsk structure in the tcp_ao_established_key() function. The issue arises because lockdep_sock_is_held() was used incorrectly on a TCP_TIME_WAIT socket that lacks the sk_lock member, leading to invalid memory access.
References
- git.kernel.org/stable/c/87bb3e719042f0030a6dad39118c6a6b2a491ad9 (opens in a new tab)
- git.kernel.org/stable/c/510db031ba6eb40134f84c90ef963ea4b6dfb878 (opens in a new tab)
- git.kernel.org/stable/c/29cf64d128c94cf98d1c69d8b2962d39db5ff4c6 (opens in a new tab)
- git.kernel.org/stable/c/03cb001ef87b3f8d859cf7f96329acf3d6235d29 (opens in a new tab)