libarchive 3.4.1 through 3.5.1 has a use-after-free in copystring (called from douncompressblock and processblock).
CVE-2021-36976
libarchive 3.4.1 through 3.5.1 has a use-after-free in copystring (called from douncompressblock and processblock).
Assessment
- CVSS
- Not yet scored
- Severity
- Unscored
- EPSS
- 2.85% chance of exploitation in the next 30 days
- Known exploited
- Not listed in CISA KEV
- Exploit availability
- Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
- Published
- 20 July 2021
- Last updated
- 2 November 2026
- Assigner
- mitre
At the source
References
- https://github.com/google/oss-fuzz-vulns/blob/main/vulns/libarchive/OSV-2021-557.yaml
- https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=32375
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SE5NJQNM22ZE5Z55LPAGCUHSBQZBKMKC/
- https://support.apple.com/kb/HT213183
- https://support.apple.com/kb/HT213182
- https://support.apple.com/kb/HT213193
- http://seclists.org/fulldisclosure/2022/Mar/28
- http://seclists.org/fulldisclosure/2022/Mar/29
- http://seclists.org/fulldisclosure/2022/Mar/27
- https://security.gentoo.org/glsa/202208-26
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