CVE-2026-99055: Linux kernel · tcp: reject net_iov in zerocopy receive mapping hints
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in 563d3564513496b9ce3b3ba7a5154427554d0f06 : patch Linux kernel soon.
Data as of 26 Oct 2026, 13:07 UTC
Rated High by Threat Radar's AI analysis · CVSS not yet scored by NVD
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 563d3564513496b9ce3b3ba7a5154427554d0f06, 8b1f0af1fd5fd113432233ed8a3862ee7c30a84f, 3aa6f536a95eb0617c313ae2eb76fdfa85331f85 +1
Exploitation evidence
Disclosed: evidence found.
CVE published 23 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 2026.
What to do
Upgrade Linux kernel to 563d3564513496b9ce3b3ba7a5154427554d0f06, 8b1f0af1fd5fd113432233ed8a3862ee7c30a84f, 3aa6f536a95eb0617c313ae2eb76fdfa85331f85 or 1c7463ac0e99cc91c4eecc1b69a740ef1a619932.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in– |
AI-suggested
A fix is available and has been applied in versions after 6.12, as indicated by the fixed commits. Users should update to a patched Linux kernel version containing these fixes to prevent kernel panic caused by this vulnerability.
Description
A vulnerability in the Linux kernel TCP zerocopy receive path was fixed by rejecting net_iov fragments before page mapping. The flaw caused a null pointer dereference in can_map_frag() when processing unreadable net_iov fragments, leading to kernel panic under certain conditions. The issue affects Linux kernel version 6.12 and was resolved by adding a guard to reject net_iov fragments early.
References
- git.kernel.org/stable/c/563d3564513496b9ce3b3ba7a5154427554d0f06 (opens in a new tab)
- git.kernel.org/stable/c/1c7463ac0e99cc91c4eecc1b69a740ef1a619932 (opens in a new tab)
- git.kernel.org/stable/c/3aa6f536a95eb0617c313ae2eb76fdfa85331f85 (opens in a new tab)
- git.kernel.org/stable/c/8b1f0af1fd5fd113432233ed8a3862ee7c30a84f (opens in a new tab)