{"id":"UBUNTU-CVE-2026-49477","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.","modified":"2026-07-15T19:47:27.072146364Z","published":"2026-07-14T21:17:00Z","upstream":["CVE-2026-49477"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-49477"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-49477"},{"type":"REPORT","url":"https://github.com/facelessuser/soupsieve/commit/eb4397618709186c109400448c6043b728217dc3"},{"type":"REPORT","url":"https://github.com/facelessuser/soupsieve/releases/tag/2.8.4"},{"type":"REPORT","url":"https://github.com/facelessuser/soupsieve/security/advisories/GHSA-836r-79rf-4m37"}],"affected":[{"package":{"name":"soupsieve","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/soupsieve?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.9.2+dfsg-2ubuntu1","1.9.4+dfsg-1","1.9.5+dfsg-1"],"ecosystem_specific":{"binaries":[{"binary_name":"python-soupsieve","binary_version":"1.9.5+dfsg-1"},{"binary_name":"python3-soupsieve","binary_version":"1.9.5+dfsg-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-49477.json"}},{"package":{"name":"soupsieve","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/soupsieve?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.2.1-2","2.3-1","2.3.1-1"],"ecosystem_specific":{"binaries":[{"binary_version":"2.3.1-1","binary_name":"python3-soupsieve"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-49477.json"}},{"package":{"name":"soupsieve","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/soupsieve?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.4.1-2","2.5-1"],"ecosystem_specific":{"binaries":[{"binary_version":"2.5-1","binary_name":"python3-soupsieve"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-49477.json"}},{"package":{"name":"soupsieve","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/soupsieve?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.7-2","2.8.1-1","2.8.3-1"],"ecosystem_specific":{"binaries":[{"binary_name":"python3-soupsieve","binary_version":"2.8.3-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-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"},{"type":"Ubuntu","score":"medium"}]}