{"id":"AZL-103325","summary":"CVE-2026-86000 affecting package python-soupsieve 2.6-3","details":"Soup Sieve is a CSS selector library designed to be used with Beautiful Soup 4. Prior to 2.9, the selector parser in src/soupsieve/css_parser.py defines IDENTIFIER with adjacent quantified groups over overlapping character classes, and VALUE embeds IDENTIFIER for attribute selectors. When an attacker-controlled selector contains a long identifier or unquoted attribute-value run followed by input that makes the overall match fail, the regular expression engine explores quadratically many splits between the overlapping groups. User-controlled selectors can reach this path through soupsieve.compile(), soupsieve.select(), or BeautifulSoup.select(), while applications using only hard-coded selectors are unaffected. The resulting CPU consumption can hold the Python GIL, exhaust application workers, and stall a service; successful plain identifier matches are linear, and the issue does not cause memory corruption or code execution. The issue is fixed in version 2.9.","modified":"2026-09-22T05:33:10Z","published":"2026-09-17T16:18:16Z","upstream":["CVE-2026-86000"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-86000"}],"affected":[{"package":{"name":"python-soupsieve","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/python-soupsieve"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"2.6-3"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-103325.json"}}],"schema_version":"1.9.0"}