CVE-2021-33909
Description
fs/seq_file.c in the Linux kernel 3.16 through 5.13.x before 5.13.4 does not properly restrict seq buffer allocations, leading to an integer overflow, an Out-of-bounds Write, and escalation to root by an unprivileged user, aka CID-8cae8cd89f05.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
Mitigation details
CVE-2021-33909 NameCVE-2021-33909 Descriptionfs/seq_file.c in the Linux kernel 3.16 through 5.13.x before 5.13.4 does not properly restrict seq buffer allocations, leading to an integer overflow, an Out-of-bounds Write, and escalation to root by an unprivileged user, aka CID-8cae8cd89f05. SourceCVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE…
CVE-2021-33909
| Name | CVE-2021-33909 |
| Description | fs/seq_file.c in the Linux kernel 3.16 through 5.13.x before 5.13.4 does not properly restrict seq buffer allocations, leading to an integer overflow, an Out-of-bounds Write, and escalation to root by an unprivileged user, aka CID-8cae8cd89f05. |
| Source | CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| References | DLA-2713-1, DLA-2714-1, DSA-4941-1 |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| linux (PTS) | bullseye | 5.10.223-1 | fixed |
| bullseye (security) | 5.10.257-1 | fixed | |
| bookworm | 6.1.170-3 | fixed | |
| bookworm (security) | 6.1.174-1 | fixed | |
| trixie | 6.12.86-1 | fixed | |
| trixie (security) | 6.12.90-2 | fixed | |
| forky, sid | 7.0.10-1 | 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 | 4.9.272-2 | DLA-2713-1 | ||
| linux | source | buster | 4.19.194-3 | DSA-4941-1 | ||
| linux | source | (unstable) | 5.10.46-2 | |||
| linux-4.19 | source | stretch | 4.19.194-3~deb9u1 | DLA-2714-1 |
Notes
https://www.qualys.com/2021/07/20/cve-2021-33909/sequoia-local-privilege-escalation-linux.txt
https://git.kernel.org/linus/8cae8cd89f05f6de223d63e6d15e31c8ba9cf53b
Apply commands
https://www.qualys.com/2021/07/20/cve-2021-33909/sequoia-local-privilege-escalation-linux.txthttps://git.kernel.org/linus/8cae8cd89f05f6de223d63e6d15e31c8ba9cf53bOS impact
SUSE Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | — |
Arch Fixed 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Fixed | 5.13.4.zen1-1 |
Debian Fixed 5 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Fixed | 5.10.46-2 |
| sid | Fixed | 5.10.46-2 |
| forky | Fixed | 5.10.46-2 |
| bullseye | Fixed | 5.10.46-2 |
| bookworm | Fixed | 5.10.46-2 |
Red Hat Fixed 1 release
| Version | Status | Fixed in |
|---|---|---|
| 8 | Fixed | — |
Rocky Linux Fixed 1 release
| Version | Status | Fixed in |
|---|---|---|
| 8 | Fixed | — |
References
- https://security.archlinux.org/ASA-202107-49
- https://security.archlinux.org/ASA-202107-48
- https://security.archlinux.org/ASA-202107-50
- https://security.archlinux.org/ASA-202107-51
- https://www.suse.com/security/cve/CVE-2021-33909.html
- https://errata.rockylinux.org/RLSA-2021:2714
- https://security-tracker.debian.org/tracker/CVE-2021-33909
- https://errata.almalinux.org/8/ALSA-2021-2714.html
- https://access.redhat.com/errata/RHSA-2021:2714
- https://access.redhat.com/errata/RHSA-2021:2715
- https://access.redhat.com/errata/RHSA-2021:2716
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.