CVE-2021-22555
Description
Linux Kernel contains a heap out-of-bounds write vulnerability that could allow an attacker to gain privileges or cause a DoS (via heap memory corruption) through user name space.
CISA KEV
- Vendor
- Linux
- Product
- Kernel
- Due date
- 2025-10-27
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
Exploits
Public proof-of-concept code below. AS-IS, for defenders and authorised testing only.
Exploit-DB
Linux Kernel 2.6.19 < 5.9 - 'Netfilter Local Privilege Escalation
Metasploit modules
OS impact
SUSE Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | — |
Arch Fixed 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Fixed | 5.10.31-1 |
Debian Fixed 5 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Fixed | 5.10.38-1 |
| sid | Fixed | 5.10.38-1 |
| forky | Fixed | 5.10.38-1 |
| bullseye | Fixed | 5.10.38-1 |
| bookworm | Fixed | 5.10.38-1 |
Red Hat Fixed 1 release
| Version | Status | Fixed in |
|---|---|---|
| 8 | Fixed | — |
Rocky Linux Fixed 1 release
| Version | Status | Fixed in |
|---|---|---|
| 8 | Fixed | — |
References
- https://www.suse.com/security/cve/CVE-2021-22555.html
- https://errata.rockylinux.org/RLSA-2021:3088
- https://errata.rockylinux.org/RLSA-2021:3057
- https://security-tracker.debian.org/tracker/CVE-2021-22555
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/net/netfilter/x_tables.c?id=9fa492cdc160cd27ce1046cb36f47d3b2b1efa21 ; https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/net/netfilter/x_tables.c?id=b29c457a6511435960115c0f548c4360d5f4801d ; https://security.netapp.com/advisory/ntap-20210805-0010/ ; https://github.com/google/security-research/security/advisories/GHSA-xxx5-8mvq-3528 ; https://nvd.nist.gov/vuln/detail/CVE-2021-22555
- https://errata.almalinux.org/8/ALSA-2021-3057.html
- https://access.redhat.com/errata/RHSA-2021:3044
- https://access.redhat.com/errata/RHSA-2021:3057
- https://access.redhat.com/errata/RHSA-2021:3088
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.