CVE-2026-6791 — Potential stack-based buffer clash during tilde expansion in wordexp

Affected: The GNU C Library glibc

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.

USN-8737-1 — glibc vulnerabilities

Affected: Ubuntu:22.04:LTS: glibc, Ubuntu:26.04:LTS: glibc

It was discovered that GNU C Library had a buffer overflow in the strfmon function when handling right-justification padding. An attacker could possibly use this issue to cause a denial of service or execute arbitrary code. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-19499)

It was discovered that GNU C Library had an out-of-bounds stack array access in the tdelete function. An attacker could possibly use this issue to cause a denial of service or execute arbitrary code. (CVE-2026-19542)

It was discovered that GNU C Library incorrectly handled memory when calling wordexp with the WRDE_APPEND flag. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-6368)

It was discovered that GNU C Library had a stack overflow in the wordexp function when expanding paths beginning with a tilde followed by a long username. An attacker could possibly use this issue to cause a denial of service or execute arbitrary code. (CVE-2026-6791)

It was discovered that GNU C Library had a hang in the SHIFT_JISX0213 character set converter. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-77117)

It was discovered that GNU C Library had a hang in the EUC_JISX0213 character set converter. An attacker could possibly use this issue to cause a denial of service. (CVE-2026-80489)

Most recent entries from all

CVE-2026-6791 — Potential stack-based buffer clash during tilde expansion in wordexp

USN-8737-1 — glibc vulnerabilities