Security tracker / CVE-2021-3493

CVE-2021-3493

overlayfs fs caps privilege escalation

References

• Debian security tracker
• cve.org
• https://www.openwall.com/lists/oss-security/2021/04/16/1
• https://github.com/briskets/CVE-2021-3493

Notes

 carnil> Debian ships as well a patch to allow enable unprivileged
 carnil> overlayfs mounts. Cf. #913880 present since 4.19.9-1 upload.
 carnil> One needs to explicitly load the module though with
 carnil> permit_mounts_in_userns (which will issue as well a security
 carnil> warning).

Bugs

Status

Branch	Status
upstream	released (5.11-rc1) [7c03e2cda4a584cadc398e8f6641ca9988a39d52]
6.18-upstream-stable
6.17-upstream-stable
6.12-upstream-stable
6.6-upstream-stable
6.1-upstream-stable	N/A "Fixed before branch point"
5.10-upstream-stable	needed
4.19-upstream-stable	N/A "Unprivileged users cannot mount overlayfs"
4.9-upstream-stable	N/A "Unprivileged users cannot mount overlayfs"
sid	released (5.10.38-1)
6.12-trixie-security
6.1-bookworm-security	N/A "Fixed before branch point"
5.10-bullseye-security	N/A "Fixed before branching point"
4.9-stretch-security	N/A "Unprivileged users cannot mount overlayfs"