cve.bz

CVE-2020-24240

5.5 mediumEPSS 1.3%

Medium (5.5) in gnu bison. EPSS 1.3% chance of exploitation in the next 30 days.

GNU Bison before 3.7.1 has a use-after-free in _obstack_free in lib/obstack.c (called from gram_lex) when a '\0' byte is encountered. NOTE: there is a risk only if Bison is used with untrusted input, and the observed bug happens to cause unsafe behavior with a specific compiler/architecture. The bug report was intended to show that a crash may occur in Bison itself, not that a crash may occur in code that is generated by Bison.

Severity

CVSS 3.1

5.5 medium
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
EPSS
1.3% chance of exploitation in the next 30 days; higher than 69% of CVEs (scores of 2026-10-31)
CWE
CWE-416
Published
Modified
Record from
the NVD, synced

Affected

References

Check your stackJSON