scanf %mc off-by-one heap buffer overflow

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

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.

Source published

20 Apr 2026 20:55:41 UTC

Source modified

15 Oct 2026 01:12:13 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

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