CVE-2026-34085
high
CVSS v3
7.8
CVSS v4 NEW
—
VIR risk
7.8
Description
fontconfig before 2.17.1 has an off-by-one error in allocation during sfnt capability handling, leading to a one-byte out-of-bounds write, and potentially a crash or code execution. This is in FcFontCapabilities in fcfreetype.c.
Predictions
Exploit likelihood
75%
Patch ETA
—
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
| OS | Version | Status | Fixed in |
|---|---|---|---|
| debian | bookworm | fixed | 0 |
| debian | bullseye | fixed | 0 |
| debian | forky | fixed | 0 |
| debian | sid | fixed | 0 |
| debian | trixie | fixed | 0 |
| sles | affected | |
Application impact
| Vendor | Product | Versions | Fixed |
|---|---|---|---|
| fontconfig_project | fontconfig | 2.17.0 | |
References
- https://gitlab.freedesktop.org/fontconfig/fontconfig/-/commit/b9bec06d73340f1b5727302d13ac3df307b7febc
- https://gitlab.freedesktop.org/fontconfig/fontconfig/-/merge_requests/446
- https://gitlab.freedesktop.org/fontconfig/fontconfig/-/work_items/481
- https://security-tracker.debian.org/tracker/CVE-2026-34085
- https://www.suse.com/security/cve/CVE-2026-34085.html
CWEs
CWE-193
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.