Description
Calling the scanf family of functions with a %mc (malloc'd character match) in the GNU C Library version 2.7 to version 2.43 with a format width specifier with an explicit width greater than 1024 could result in a one byte heap buffer overflow.
Affected products
gnu: glibc
References4
- sourceware.org/bugzilla/show_bug.cgi?id=CVE-2026-5450 ExploitIssue Tracking
- sourceware.org/bugzilla/show_bug.cgi?id=CVE-2026-5450 ExploitIssue Tracking
- inbox.sourceware.org/libc-announce/b11f0003-6ec1-4bd6-b9de-9e38… Third Party Advisory
- cert-portal.siemens.com/productcert/html/ssa-082556.html
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 44 · as of 13 November 2026
- CWE
- CWE-122CWE-787
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