CVE-2026-18374 (GCVE-0-2026-18374)

Vulnerability from cvelistv5 – Published: 2026-08-27 19:20 – Updated: 2026-08-28 15:37
VLAI
Summary
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.
Severity
4.9 (Medium)
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-28 15:36 UTC
CWE
  • Buffer overflow in fopen mode argument processing
  • CWE-787 - Out-of-bounds write
  • CWE-787 - Out-of-bounds Write
Assigner
glibc CNA under the redhat root
CNA scorecard C 74/100 over 16 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
The GNU C Library glibc Affected: 0 , < 2.45 (custom)
guessed Create a notification for this product.
Show details on NVD website
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