{"id":"GHSA-hmv2-79q8-fv6g","summary":"Uncontrolled Resource Consumption in urllib3","details":"The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2).","aliases":["CVE-2020-7212","PYSEC-2020-149"],"modified":"2024-11-18T22:35:00.503678Z","published":"2021-04-30T17:31:43Z","database_specific":{"cwe_ids":["CWE-400"],"severity":"HIGH","github_reviewed":true,"github_reviewed_at":"2021-04-22T22:04:31Z","nvd_published_at":"2020-03-06T20:15:00Z"},"references":[{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2020-7212"},{"type":"WEB","url":"https://github.com/urllib3/urllib3/commit/a74c9cfbaed9f811e7563cfc3dce894928e0221a"},{"type":"ADVISORY","url":"https://github.com/advisories/GHSA-hmv2-79q8-fv6g"},{"type":"WEB","url":"https://github.com/pypa/advisory-database/tree/main/vulns/urllib3/PYSEC-2020-149.yaml"},{"type":"PACKAGE","url":"https://github.com/urllib3/urllib3"},{"type":"WEB","url":"https://github.com/urllib3/urllib3/blob/master/CHANGES.rst"},{"type":"WEB","url":"https://pypi.org/project/urllib3/1.25.8"}],"affected":[{"package":{"name":"urllib3","ecosystem":"PyPI","purl":"pkg:pypi/urllib3"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"1.25.2"},{"fixed":"1.25.8"}]}],"versions":["1.25.2","1.25.3","1.25.4","1.25.5","1.25.6","1.25.7"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2021/04/GHSA-hmv2-79q8-fv6g/GHSA-hmv2-79q8-fv6g.json","last_known_affected_version_range":"\u003c= 1.25.7"}}],"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"}]}