Quick answers
- Is CVE-2026-56002 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-56002 being exploited in the wild.
- How severe is CVE-2026-56002?
- High severity, with a CVSS score of 8.5, published 8 July 2026.
- Which products and versions are affected?
- X.Org libXfont2 before 2.0.8.
- Is there a fix for CVE-2026-56002?
- A patch was published on 2026-06-01: Fix committed to GitLab repository. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-56002 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-56002?
- Check whether you run X.Org libXfont2 at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A heap-based buffer overflow exists in libXfont2's pcfReadFont() function due to insufficient validation of PCF font files. The library allocates a bitmap buffer based on the 'bitmapSizes' value provided in the file but performs subsequent writes based on per-glyph metrics without verifying they fit within the allocated space. An attacker authenticated as an X client can provide a malicious PCF font with mismatched metrics to trigger the overflow during font parsing. This can result in arbitrary code execution within the context of the X server. The issue is addressed in version 2.0.8 by validating bitmap sizes, offsets, and glyph extents against the actual buffer capacity.
Affected products
- X.Org libXfont2 before 2.0.8
Timeline
- 2026-06-01: patched: Fix committed to GitLab repository.
- 2026-07-08: advisory: X.Org Security Advisory released.
- 2026-07-08: disclosed: CVE published to NVD.