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.

The remote SUSE Linux SLED15 / SLED_SAP15 / SLES15 / SLES_SAP15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:4250-1 advisory.

    - CVE-2026-6368: invalid free via wordexp WRDE_APPEND rollback (bsc#1274726).
    - CVE-2026-6791: stack overflow in wordexp tilde expansion (bsc#1274723).
    - CVE-2026-18374: heap buffer overflow in the fopen ccs extension (bsc#1277262).
    - CVE-2026-19499: buffer overflow in strfmon right-justification padding (bsc#1276892).
    - CVE-2026-19542: out-of-bounds array write in tdelete (bsc#1276946).
    - CVE-2026-77117: SHIFT_JISX0213 decoding lacks pending character reset (bsc#1277921).
    - CVE-2026-80489: EUC_JISX0213 decoding lacks pending character reset (bsc#1277922).

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote SUSE Linux SLES12 / SLES_SAP12 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:4204-1 advisory.

    - CVE-2026-6368: wordexp WRDE_APPEND rollback restores stale we_wordv, leading to invalid free in wordfree       (bsc#1274726).
    - CVE-2026-6791: wordexp: unbounded alloca (strndupa) in parse_tilde (bsc#1274723).
    - CVE-2026-18374: overflow in the fopen ccs extension (bsc#1277262).
    - CVE-2026-19542: Fix out-of-bounds array write in tdelete (bsc#1276946).
    - CVE-2026-77117: non-progress DoS in SHIFT_JISX0213 -> UCS-4 conversion state handling (bsc#1277921).
    - CVE-2026-80489: non-progress DoS in SHIFT_JISX0213 -> UCS-4 conversion state handling (bsc#1277922).

Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Ubuntu 22.04 LTS / 26.04 LTS / Pro Realtime 22.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-8737-1 advisory.

    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)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The version of Tencent Linux installed on the remote TencentOS Server 4 host is prior to tested version. It is, therefore, affected by multiple vulnerabilities as referenced in the TSSA-2026:0850 advisory.

    Package updates are available for TencentOS Server 4 that fix the following vulnerabilities:

    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.

    CVE-2026-6368:
    Calling wordexp with WRDE_APPEND in the GNU C Library version 2.0 to version 2.43 can cause the interface     to return invalid memory in the we_wordv member, which on subsequent calls to wordfree may abort the     process.

Tenable has extracted the preceding description block directly from the Tencent Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - 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. (CVE-2026-6791)

Note that Nessus relies on the presence of the package as reported by the vendor.

ID	Name	Product	Family	Type	Severity
347899	SUSE SLED15: glibc / glibc-32bit / glibc-devel / glibc-devel-32bit / etc (SUSE-SU-2026:4250-1)	Nessus	SuSE Local Security Checks	Local	critical
346800	SUSE SLES12: glibc / glibc-32bit / glibc-devel / glibc-devel-32bit / etc (SUSE-SU-2026:4204-1)	Nessus	SuSE Local Security Checks	Local	critical
344610	Ubuntu 22.04 LTS / 26.04 LTS / Pro Realtime 22.04 LTS : GNU C Library vulnerabilities (USN-8737-1)	Nessus	Ubuntu Local Security Checks	Local	critical
339169	TencentOS Server 4: glibc (TSSA-2026:0850)	Nessus	Tencent Local Security Checks	Local	critical
334155	Linux Distros Unpatched Vulnerability : CVE-2026-6791	Nessus	Misc.	Local	critical

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