CVE-2026-56003
Last modified
CVE-2026-56003 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. A heap buffer overflow due to missing size checking in the property buffer when parsing PCF files in libXfont2 ComputeScaledProperties() before libXfont2 before 2.0.8 could be used by attackers using authenticated X clients to execute code within the X server.. EPSS estimates a 0.58% chance of exploitation in the next 30 days.
Description
A heap buffer overflow due to missing size checking in the property buffer when parsing PCF files in libXfont2 ComputeScaledProperties() before libXfont2 before 2.0.8 could be used by attackers using authenticated X clients to execute code within the X server.
Metrics
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| X | Libxfont | >= 2.0.0, < 2.0.8 |
References
- https://www.openwall.com/lists/oss-security/2026/07/08/1Mailing List, Patch, Third Party Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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