Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
Linux kernel versions from 4.11 up to, but not including, the fixed releases (6.1.191, 6.6.160, 6.12.114, 6.18.57 and their stable series) are affected. The ESP IPsec output path can drop a page reference that the socket buffer never acquired when it carries managed frags, such as those from io_uring SEND_ZC with registered buffers. This can underflow the page reference count and free a page still in use. The source gives few details on how an attacker reaches this path. Upgrade to a fixed kernel version; no workaround is listed.
Not analysed yet
We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 7.8 | High | 3.1 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H | CNA (Linux) |
- CISA KEV Not listed.
- EPSS 0.0018, the 7th percentile, on 13 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
Sources
References from the CNA
- git.kernel.org/stable/c/cb375965800d474c0281a2e92c43c724fce9f463
- git.kernel.org/stable/c/201bdf10ae92e7cbd524adf8c0323e2a963d5fd7
- git.kernel.org/stable/c/3ec55f0c8a6a543cf660584d1346e11f6311ee59
- git.kernel.org/stable/c/1ad6456898f6e6cf58be83bdb607acb1119a9cd1
- git.kernel.org/stable/c/26b6b14c7a0368e317a1e9fb5144ebe6f8d495cf
- git.kernel.org/stable/c/21697720ff43b8dfa25b8e8d9ca7f56f4597fc80