{"action":"Upgrade icalendar to 7.1.3 or later.","affected":[{"fixed":"7.1.3","introduced":"7.1.0"}],"component":"icalendar","cve_ids":["CVE-2026-55099"],"ecosystem":"PyPI","epss":0.0063,"exploited":false,"fixed_versions":["7.1.3"],"ghsa_id":"GHSA-cv84-9p8j-fj68","id":"tcs_01M5KH85MANR8NRSS2QDXMB520","modified_at":"2026-09-10T12:15:04.992644758Z","published_at":"2026-09-10T09:44:57.047436Z","references":["https://osv.dev/vulnerability/PYSEC-2026-3851","https://github.com/collective/icalendar/security/advisories/GHSA-cv84-9p8j-fj68","https://github.com/collective/icalendar/commit/b6b2608ae3af6de40695b4e40f71847485aa0b49","https://github.com/collective/icalendar/commit/cad40cd112c93fd142ec12cc5b37445a849b8a79","https://github.com/collective/icalendar","https://github.com/collective/icalendar/releases/tag/v7.1.3","https://pypi.org/project/icalendar","https://github.com/advisories/GHSA-cv84-9p8j-fj68","https://nvd.nist.gov/vuln/detail/CVE-2026-55099"],"severity":{"label":"high","score":7.5},"sources":[{"source":"osv","source_id":"PYSEC-2026-3851","url":"https://osv.dev/vulnerability/PYSEC-2026-3851"}],"summary":"icalendar has Algorithmic Complexity in Equality"}