{"id":"CVE-2026-49477","summary":"Soup Sieve: Regular Expression Denial of Service (ReDoS) in soupsieve Selector Parser","details":"Soup Sieve is a CSS selector library designed to be used with Beautiful Soup 4. Prior to 2.8.4, the CSS selector parser in soupsieve contains a regular expression vulnerable to catastrophic backtracking when processing an attribute selector with an unterminated quoted value in soupsieve/css_parser.py, allowing an attacker who can supply untrusted CSS selector strings to soupsieve.compile() or Beautiful Soup .select() / .select_one() to cause CPU exhaustion and denial of service. This issue is fixed in version 2.8.4.","aliases":["GHSA-836r-79rf-4m37","PYSEC-2026-3072"],"modified":"2026-07-17T18:29:41.061668251Z","published":"2026-07-14T20:51:29.369Z","related":["CGA-9cx6-r7p8-hvrm","SUSE-SU-2026:22660-1","openSUSE-SU-2026:21342-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49477.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-1333","CWE-400"]},"references":[{"type":"WEB","url":"https://github.com/facelessuser/soupsieve/releases/tag/2.8.4"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49477.json"},{"type":"ADVISORY","url":"https://github.com/facelessuser/soupsieve/security/advisories/GHSA-836r-79rf-4m37"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-49477"},{"type":"FIX","url":"https://github.com/facelessuser/soupsieve/commit/eb4397618709186c109400448c6043b728217dc3"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/facelessuser/soupsieve","events":[{"introduced":"0"},{"fixed":"eb4397618709186c109400448c6043b728217dc3"},{"fixed":"28108ab805818c832d9568142a99844fd95a0d39"}],"database_specific":{"source":["AFFECTED_FIELD","REFERENCES"],"extracted_events":[{"introduced":"0"},{"fixed":"2.8.4"}]}}],"versions":["2.8.3","2.8.2","2.8.1","2.8","2.7","2.6","2.5","2.4.1","2.4","2.3.2.post1","2.3.2","2.3.1","2.3","2.2.1","2.2","2.1.0","2.0.1","2.0.0","1.9.4","1.9.3","1.9.2","1.9.1","1.9.0","1.8.0","1.7.3","1.7.2","1.7.1","1.7.0","1.6.1","1.6.0","1.5.0","1.4.0","1.3.1","1.3.0","1.2.1","1.2.0","1.1.0","1.0.2","1.0.1","1.0.0","1.0.0b2","1.0.0b1","0.6.0","0.5.3","0.5.2","0.5.1","0.5.0","0.4.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-49477.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}