CVE-2026-6791

When expanding paths that begin with a tilde (~) followed by a username, the internal parse_tilde function extracts the username to determine the user's home directory. The implementation allocates memory for this username directly on the stack using the strndupa macro. Because the size of this allocation was determined by the length of the user-supplied input without any bounds checks, passing an excessively long username e.g. thousands of characters, forces the thread to exhaust its stack space. Thus if an application passes untrusted, attacker-controlled input to the wordexp function, an attacker can trigger a stack clash.

CVSS

No CVSS.

References

Link	Resource
https://sourceware.org/bugzilla/show_bug.cgi?id=34091

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-10 19:17

Updated : 2026-09-03 16:43

NVD link : CVE-2026-6791

Mitre link : CVE-2026-6791

CVE.ORG link : CVE-2026-6791

JSON object : View

Products Affected

No product.

CWE

CWE-121

Stack-based Buffer Overflow

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