cvedb.io
CVE-2026-50256
HIGH · CVSS 7.8
EPSS exploitation probability: 5%
Published 2026-06-05T12:16:38.727 · Last modified 2026-06-24T11:16:34.483

Summary

A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland. A mismatch between the X server and the libXfont2 library's maximum font name length can cause a stack buffer overflow during font alias resolution. The server allocates a 256 byte stack buffer but libXfont2's alias target name length is 1024 bytes. A font alias name between 257 and 1023 bytes causes the X server to copy that name into the undersized stack buffer without further checks. This may be used to crash the server, or for privilege escalation if the X server runs as root.

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.