{"id":"CVE-2021-33503","published":"2021-06-29T10:55:35Z","modified":"2024-08-03T23:50:42Z","title":"An issue was discovered in urllib3 before 1.26.5","vendor":null,"product":null,"tier":"tail","description":{"text":"An issue was discovered in urllib3 before 1.26.5. When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.","provenance":"source","from":"CVE.org"},"cvss":null,"epss":{"score":0.03273,"percentile":0.88401,"provenance":"source"},"cwes":[],"references":[{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FMUGWEAUYGGHTPPXT6YBD53WYXQGVV73/","tags":["vendor-advisory","x_refsource_FEDORA"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6SCV7ZNAHS3E6PBFLJGENCDRDRWRZZ6W/","tags":["vendor-advisory","x_refsource_FEDORA"]},{"url":"https://security.gentoo.org/glsa/202107-36","tags":["vendor-advisory","x_refsource_GENTOO"]},{"url":"https://www.oracle.com/security-alerts/cpuoct2021.html","tags":["x_refsource_MISC"]},{"url":"https://github.com/advisories/GHSA-q2q7-5pp4-w6pg","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/urllib3/urllib3/commit/2d4a3fee6de2fa45eb82169361918f759269b4ec","tags":["x_refsource_CONFIRM"]}],"priority":{"score":17.7,"factors":[{"name":"EPSS percentile","points":17.68}]},"affected":[{"ecosystem":"PyPI","package":"urllib3","vulnerableRanges":[">=1.25.4, <1.26.5"],"patched":["1.26.5"],"from":["GHSA-q2q7-5pp4-w6pg","PYSEC-2021-108"],"provenance":"source"}],"euvd":{"id":"EUVD-2021-0456","exploited":false,"provenance":"source"},"lineage":{"familyId":"fam-urllib3-cve-2018-20060","parents":[{"from":"CVE-2019-11324","to":"CVE-2021-33503","relation":"related","confidence":"medium","kind":"lineage","evidence":[{"kind":"same-code","provenance":"machine","files":["src/urllib3/util/ssl_.py"],"commits":["https://github.com/urllib3/urllib3/commit/1efadf43dc63317cd9eaa3e0fdb9e05ab07254b1","https://github.com/urllib3/urllib3/commit/2d4a3fee6de2fa45eb82169361918f759269b4ec","https://github.com/urllib3/urllib3/commit/5b047b645f5f93900d5e2fc31230848c25eb1f5f"],"basis":"rarely changed file"}]},{"from":"CVE-2020-7212","to":"CVE-2021-33503","relation":"related","confidence":"medium","kind":"lineage","evidence":[{"kind":"same-code","provenance":"machine","files":["src/urllib3/util/url.py"],"commits":["https://github.com/urllib3/urllib3/commit/a74c9cfbaed9f811e7563cfc3dce894928e0221a","https://github.com/urllib3/urllib3/commit/2d4a3fee6de2fa45eb82169361918f759269b4ec","https://github.com/urllib3/urllib3/commit/5b047b645f5f93900d5e2fc31230848c25eb1f5f"],"basis":"shared function","functions":["parse_url","split_first"]}]}],"children":[{"from":"CVE-2021-33503","to":"CVE-2023-45803","relation":"related","confidence":"medium","kind":"lineage","evidence":[{"kind":"same-code","provenance":"machine","files":["src/urllib3/connectionpool.py"],"commits":["https://github.com/urllib3/urllib3/commit/2d4a3fee6de2fa45eb82169361918f759269b4ec","https://github.com/urllib3/urllib3/commit/5b047b645f5f93900d5e2fc31230848c25eb1f5f","https://github.com/urllib3/urllib3/commit/4e98d57809dacab1cbe625fddeec1a290c478ea9","https://github.com/urllib3/urllib3/commit/4e50fbc5db74e32cabd5ccc1ab81fc103adfe0b3"],"basis":"rarely changed file"}]}],"packageHistory":[{"cve":"CVE-2020-7212","published":"2020-03-06","fixed":"1.25.8","kev":false},{"cve":"CVE-2020-26137","published":"2020-09-29","fixed":"1.25.9","kev":false},{"cve":"CVE-2021-28363","published":"2021-03-15","fixed":"1.26.4","kev":false,"link":{"from":"CVE-2021-28363","to":"CVE-2021-33503","relation":"successor","confidence":"low","kind":"sequence","evidence":[{"kind":"version-step","provenance":"source","package":"PyPI:urllib3","fromFixed":"1.26.4","toFixed":"1.26.5","daysApart":106}]}},{"cve":"CVE-2021-33503","published":"2021-06-29","fixed":"1.26.5","kev":false},{"cve":"CVE-2023-43804","published":"2023-10-04","fixed":"2.0.6","kev":false},{"cve":"CVE-2023-45803","published":"2023-10-17","fixed":"2.0.7","kev":false},{"cve":"CVE-2024-37891","published":"2024-06-17","fixed":"2.2.2","kev":false}],"package":"PyPI:urllib3"}}