CVE-2026-99270: Linux kernel · tcp: Fix potential UAF in reqsk_timer_handler().
Source GCVE Database
Not known to be exploited : upgrade to 97c8a3c1f73d828de43a5a88e8a9a143efb2b661 or 4.2 soon.
Data as of 3 Nov 2026, 16:45 UTC
Rated High by Threat Radar's AI analysis · CVSS not yet scored by NVD
Thin evidence
One scorer or none- Patch
- Available – fixed in 97c8a3c1f73d828de43a5a88e8a9a143efb2b661, 4.2
Exploitation evidence
Disclosed: evidence found.
CVE published 3 Nov 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
Upgrade Linux kernel to 97c8a3c1f73d828de43a5a88e8a9a143efb2b661 or 4.2.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in– |
AI-suggested
A fix has been implemented in the Linux kernel to address this issue by ensuring the new request socket's timer is stopped before freeing the socket. Users should apply the official kernel update that includes this fix once available.
Description
A use-after-free (UAF) vulnerability in the Linux kernel's TCP socket migration handling was fixed. The flaw occurs in the reqsk_timer_handler() function when TCP socket migration fails at inet_ehash_insert(), leading to premature freeing of a new request socket (reqsk) without properly stopping its timer. This can cause a UAF condition due to a missed timer deletion.