CVE-2026-18374

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.

References

https://sourceware.org/git/?p=glibc.git;a=blob_plain;f=advisories/GLIBC-SA-2026-0015

https://sourceware.org/bugzilla/show_bug.cgi?id=34574

http://www.openwall.com/lists/oss-security/2026/08/27/6

Details

Source: Mitre, NVD

Risk Information

CVSS v2

CVSS v3

EPSS