{"id":"GHSA-g3pv-pj5f-3hfq","summary":"mechanize Regular Expression Denial of Service vulnerability","details":"mechanize, a library for automatically interacting with HTTP web servers, contains a regular expression that is vulnerable to regular expression denial of service (ReDoS) prior to version 0.4.6. If a web server responds in a malicious way, then mechanize could crash. Version 0.4.6 has a patch for the issue.","aliases":["CVE-2021-32837","PYSEC-2023-25"],"modified":"2025-12-22T23:03:24.534496Z","published":"2023-01-18T00:30:18Z","database_specific":{"github_reviewed_at":"2023-01-20T23:35:49Z","nvd_published_at":"2023-01-17T22:15:00Z","cwe_ids":["CWE-1333"],"severity":"HIGH","github_reviewed":true},"references":[{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-32837"},{"type":"WEB","url":"https://github.com/python-mechanize/mechanize/commit/dd05334448e9f39814bab044d2eaa5ef69b410d6"},{"type":"WEB","url":"https://github.com/pypa/advisory-database/tree/main/vulns/mechanize/PYSEC-2023-25.yaml"},{"type":"PACKAGE","url":"https://github.com/python-mechanize/mechanize"},{"type":"WEB","url":"https://github.com/python-mechanize/mechanize/blob/3acb1836f3fd8edc5a758a417dd46b53832ae3b5/mechanize/_urllib2_fork.py#L878-L879"},{"type":"WEB","url":"https://github.com/python-mechanize/mechanize/releases/tag/v0.4.6"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2023/06/msg00022.html"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2025/12/msg00028.html"},{"type":"ADVISORY","url":"https://securitylab.github.com/advisories/GHSL-2021-108-python-mechanize-mechanize"}],"affected":[{"package":{"name":"mechanize","ecosystem":"PyPI","purl":"pkg:pypi/mechanize"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.4.6"}]}],"versions":["0.0.10a","0.0.11a","0.0.1a","0.0.8a","0.0.9a","0.1.0a","0.1.10","0.1.11","0.1.1a","0.1.2b","0.1.4b","0.1.5b","0.1.6b","0.1.7b","0.1.8","0.1.9","0.2.0","0.2.1","0.2.2","0.2.3","0.2.4","0.2.5","0.3.0","0.3.1","0.3.2","0.3.3","0.3.4","0.3.5","0.3.6","0.3.7","0.4.0","0.4.1","0.4.2","0.4.3","0.4.4","0.4.5"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2023/01/GHSA-g3pv-pj5f-3hfq/GHSA-g3pv-pj5f-3hfq.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"}]}