CVE-2026-18374 (GCVE-0-2026-18374)
Vulnerability from cvelistv5
Published
2026-08-27 19:20
Modified
2026-08-28 15:37
CWE
  • Buffer overflow in fopen mode argument processing
  • CWE-787 - Out-of-bounds write
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.
Impacted products
Vendor Product Version
The GNU C Library glibc Version: 0   < 2.45
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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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