{"id":"CVE-2026-49477","state":"PUBLISHED","title":"Soup Sieve: Regular Expression Denial of Service (ReDoS) in soupsieve Selector Parser","description":"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.","publishedAt":"2026-07-14T20:51:29.369Z","updatedAt":"2026-07-21T14:49:40.914Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["facelessuser soupsieve"],"affected":[{"vendor":"facelessuser","product":"soupsieve","versions":[{"version":"< 2.8.4","status":"affected"}]}],"references":["https://github.com/facelessuser/soupsieve/security/advisories/GHSA-836r-79rf-4m37","https://github.com/facelessuser/soupsieve/commit/eb4397618709186c109400448c6043b728217dc3","https://github.com/facelessuser/soupsieve/releases/tag/2.8.4"],"weaknesses":["CWE-400","CWE-1333"],"ingestedAt":"2026-10-29T20:12:07.131Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/49xxx/CVE-2026-49477.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-49477","state":"PUBLISHED","datePublished":"2026-07-14T20:51:29.369Z","dateUpdated":"2026-07-21T14:49:40.914Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-05-30T04:17:43.095Z"},"containers":{"cna":{"title":"Soup Sieve: Regular Expression Denial of Service (ReDoS) in soupsieve Selector Parser","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"facelessuser","product":"soupsieve","versions":[{"version":"< 2.8.4","status":"affected"}]}],"references":[{"url":"https://github.com/facelessuser/soupsieve/security/advisories/GHSA-836r-79rf-4m37","name":"https://github.com/facelessuser/soupsieve/security/advisories/GHSA-836r-79rf-4m37","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/facelessuser/soupsieve/commit/eb4397618709186c109400448c6043b728217dc3","name":"https://github.com/facelessuser/soupsieve/commit/eb4397618709186c109400448c6043b728217dc3","tags":["x_refsource_MISC"]},{"url":"https://github.com/facelessuser/soupsieve/releases/tag/2.8.4","name":"https://github.com/facelessuser/soupsieve/releases/tag/2.8.4","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-400","lang":"en","description":"CWE-400: Uncontrolled Resource Consumption","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-1333","lang":"en","description":"CWE-1333: Inefficient Regular Expression Complexity","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-07-14T20:51:29.369Z"},"source":{"advisory":"GHSA-836r-79rf-4m37","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/facelessuser/soupsieve/security/advisories/GHSA-836r-79rf-4m37","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-21T14:49:25.096784Z","id":"CVE-2026-49477","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-07-21T14:49:40.914Z"}}]}}}