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.
References
- https://nvd.nist.gov/vuln/detail/CVE-2021-32837
- https://github.com/python-mechanize/mechanize/commit/dd05334448e9f39814bab044d2eaa5ef69b410d6
- https://github.com/python-mechanize/mechanize/blob/3acb1836f3fd8edc5a758a417dd46b53832ae3b5/mechanize/_urllib2_fork.py#L878-L879
- https://github.com/python-mechanize/mechanize/releases/tag/v0.4.6
- https://securitylab.github.com/advisories/GHSL-2021-108-python-mechanize-mechanize/
- https://github.com/advisories/GHSA-g3pv-pj5f-3hfq