CVE-2025-21836

MEDIUM

Linux Kernel 5.19-6.6.78, 6.7-6.12.15, 6.13-6.13.3 - Memory Corruption via io_uring Buffer List Reuse

Title source: llm

Description

In the Linux kernel, the following vulnerability has been resolved: io_uring/kbuf: reallocate buf lists on upgrade IORING_REGISTER_PBUF_RING can reuse an old struct io_buffer_list if it was created for legacy selected buffer and has been emptied. It violates the requirement that most of the field should stay stable after publish. Always reallocate it instead.

References (5)

Core 5

Core References

Patch

https://git.kernel.org/stable/c/146a185f6c05ee263db715f860620606303c4633

Patch

https://git.kernel.org/stable/c/7d0dc28dae836caf7645fef62a10befc624dd17b

Patch

https://git.kernel.org/stable/c/2a5febbef40ce968e295a7aeaa5d5cbd9e3e5ad4

Patch

https://git.kernel.org/stable/c/8802766324e1f5d414a81ac43365c20142e85603

Various Sources

https://u1f383.github.io/slides/talks/2025_Hexacon-Deja_Vu_in_Linux_io_uring_Breaking_Memory_Sharing_Again_After_Generations_of_Fixes.pdf

Scores

CVSS v3 5.5

EPSS 0.0022

EPSS Percentile 12.7%

Attack Vector LOCAL

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Details

Status published

Products (15)

linux/Kernel 5.19.0 - 6.6.79linux

linux/Kernel 6.13.0 - 6.13.4linux

linux/Kernel 6.7.0 - 6.12.16linux

Linux/Linux < 5.19

Linux/Linux 2fcabce2d7d34f69a888146dab15b36a917f09d4 - 146a185f6c05ee263db715f860620606303c4633

Linux/Linux 2fcabce2d7d34f69a888146dab15b36a917f09d4 - 2a5febbef40ce968e295a7aeaa5d5cbd9e3e5ad4

Linux/Linux 2fcabce2d7d34f69a888146dab15b36a917f09d4 - 7d0dc28dae836caf7645fef62a10befc624dd17b

Linux/Linux 2fcabce2d7d34f69a888146dab15b36a917f09d4 - 8802766324e1f5d414a81ac43365c20142e85603

Linux/Linux 5.19

Linux/Linux 6.12.16 - 6.12.*

... and 5 more

Published Mar 07, 2025

Tracked Since Feb 18, 2026