CVE-2026-18374 — MEDIUM (4.9)

Vulnerability Description

Passing an effectively empty string to the `,ccs=` syntax extension of the mode argument in the `fopen` function in the GNU C Library version 2.45 or earlier may result in a heap buffer overflow when the mode string input to the function is attacker controlled. This usage pattern is not seen in applications in common GNU/Linux distributions and applications that process user-supplied values for `ccs` should not pass them through without validation.

CVSS Score

4.9

MEDIUM

CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L

Attack Vector

LOCAL

Attack Complexity

HIGH

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

LOW

Integrity

LOW

Availability

LOW

Related Weaknesses (CWE)

CWE-787

References

FAQ

What is CVE-2026-18374?

CVE-2026-18374 is a vulnerability with a CVSS score of 4.9 (MEDIUM). Passing an effectively empty string to the `,ccs=` syntax extension of the mode argument in the `fopen` function in the GNU C Library version 2.45 or earlier may result in a heap buffer overflow when ...

How severe is CVE-2026-18374?

CVE-2026-18374 has been rated MEDIUM with a CVSS base score of 4.9/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-18374?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.