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 c…

Code

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Timeline

Detection, updates, and resolution for this record.

1. Mar 25, 2026 · NIST NVD

   Detected

   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.

2. Jun 17, 2026 · NIST NVD

   Updated

   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.

Affected

• cpe fontconfig project/fontconfig2.17.0

Sources

• CVE.orgVulnerability recordCVE-2026-34085

  Official CVE identifier

  cve.org
• NIST NVDVulnerability recordCVE-2026-34085

  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.

  nvd.nist.gov

References

• Patch · gitlab.freedesktop.org
• Patch · gitlab.freedesktop.org
• Issue Tracking · gitlab.freedesktop.org