CVE-2026-6100
Description
Use-after-free (UAF) was possible in the `lzma.LZMADecompressor`, `bz2.BZ2Decompressor`, and `gzip.GzipFile` when a memory allocation fails with a `MemoryError` and the decompression instance is re-used. This scenario can be triggered if the process is under memory pressure. The fix cleans up the dangling pointer in this specific error condition. The vulnerability is only present if the program re-uses decompressor instances across multiple decompression calls even after a `MemoryError` is raised during decompression. Using the helper functions to one-shot decompress data such as `lzma.decompress()`, `bz2.decompress()`, `gzip.decompress()`, and `zlib.decompress()` are not affected as a new decompressor instance is used per call. If the decompressor instance is not re-used after an error condition, this usage is similarly not vulnerable.
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.
OS impact
SUSE Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | — |
AlmaLinux Fixed 1 release
| Version | Status | Fixed in |
|---|---|---|
| 9 | Fixed | python3.11-3.11.13-9.el9_8.aarch64.rpm |
Debian Fixed 5 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Fixed | 0 |
| sid | Fixed | 0 |
| forky | Fixed | 0 |
| bullseye | Fixed | 0 |
| bookworm | Fixed | 0 |
Red Hat Fixed 2 releases
| Version | Status | Fixed in |
|---|---|---|
| 9 | Fixed | — |
| 8 | Fixed | — |
Rocky Linux Fixed 1 release
| Version | Status | Fixed in |
|---|---|---|
| 9 | Fixed | — |
References
- https://access.redhat.com/errata/RHSA-2026:10745
- https://access.redhat.com/errata/RHSA-2026:10774
- https://access.redhat.com/errata/RHSA-2026:10949
- https://access.redhat.com/errata/RHSA-2026:19175
- https://access.redhat.com/errata/RHSA-2026:19176
- https://access.redhat.com/errata/RHSA-2026:19177
- https://access.redhat.com/errata/RHSA-2026:19216
- https://www.suse.com/security/cve/CVE-2026-6100.html
- https://security-tracker.debian.org/tracker/CVE-2026-6100
- https://access.redhat.com/errata/RHSA-2026:11062
- https://bugzilla.redhat.com/2457932
- https://bugzilla.redhat.com/2458049
- https://errata.almalinux.org/8/ALSA-2026-11062.html
- https://access.redhat.com/errata/RHSA-2026:11077
- https://errata.almalinux.org/8/ALSA-2026-11077.html
- https://errata.almalinux.org/9/ALSA-2026-10745.html
- https://errata.almalinux.org/9/ALSA-2026-10774.html
- https://errata.almalinux.org/9/ALSA-2026-10949.html
- https://bugzilla.redhat.com/2449649
- https://errata.almalinux.org/9/ALSA-2026-19175.html
- https://errata.almalinux.org/9/ALSA-2026-19216.html
- https://bugzilla.redhat.com/2431367
- https://bugzilla.redhat.com/2444691
- https://bugzilla.redhat.com/2448168
- https://bugzilla.redhat.com/2448181
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.