| Name | CVE-2021-41073 |
| Description | loop_rw_iter in fs/io_uring.c in the Linux kernel 5.10 through 5.14.6 allows local users to gain privileges by using IORING_OP_PROVIDE_BUFFERS to trigger a free of a kernel buffer, as demonstrated by using /proc/<pid>/maps for exploitation. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| References | DSA-4978-1 |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| linux (PTS) | buster | 4.19.249-2 | fixed |
| buster (security) | 4.19.289-2 | fixed |
| bullseye | 5.10.178-3 | fixed |
| bullseye (security) | 5.10.191-1 | fixed |
| bookworm | 6.1.38-1 | fixed |
| bookworm (security) | 6.1.52-1 | fixed |
| sid, trixie | 6.5.3-1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|
| linux | source | stretch | (not affected) | | | |
| linux | source | buster | (not affected) | | | |
| linux | source | bullseye | 5.10.46-5 | | DSA-4978-1 | |
| linux | source | (unstable) | 5.14.6-2 | | | |
Notes
[buster] - linux <not-affected> (Vulnerable code introduced later)
[stretch] - linux <not-affected> (Vulnerable code introduced later)
https://www.openwall.com/lists/oss-security/2021/09/18/2
https://www.graplsecurity.com/post/iou-ring-exploiting-the-linux-kernel
https://starlabs.sg/blog/2022/06/io_uring-new-code-new-bugs-and-a-new-exploit-technique/