CVE-2026-18374

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 v3 4.9 MEDIUM

4.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.4 / Impact : 3.4

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://sourceware.org/bugzilla/show_bug.cgi?id=34574
https://sourceware.org/git/?p=glibc.git;a=blob_plain;f=advisories/GLIBC-SA-2026-0015
http://www.openwall.com/lists/oss-security/2026/08/27/6

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-27 20:17

Updated : 2026-09-03 16:43

NVD link : CVE-2026-18374

Mitre link : CVE-2026-18374

CVE.ORG link : CVE-2026-18374

JSON object : View

Products Affected

No product.

CWE

CWE-787

Out-of-bounds Write

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