Use After Free in Gnu Bison
CVE-2020-24240
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 u…
Vulnerability class: Use-After-Free
EPSS: 0.013 (66.7th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H.
Affected products
- Gnu Bison — versions 3.7
- N/a — versions n/a
Weakness classification (CWE)
References
- cve@mitre.org (Patch, Third Party Advisory, x_refsource_MISC)
- cve@mitre.org (Mailing List, x_refsource_MISC, Vendor Advisory)
- cve@mitre.org (Third Party Advisory, x_refsource_MISC)
Frequently asked questions
- What is CVE-2020-24240?
- CVE-2020-24240 is a medium-severity vulnerability in Gnu Bison, classified under Use After Free. CVSS score: 5.5/10. Published 2020-08-25.
- How severe is CVE-2020-24240?
- Medium severity. CVSS v3 base score is 5.5 out of 10.