{"schema":"threatline.record/2","record":{"id":"CVE-2026-109391","aliases":[],"summary":"Square Squash through commit e73f280 Unauthenticated YAML Deserialization via Symbolication API","details":"Square Squash through commit e73f280 contains an insecure deserialization vulnerability that allows unauthenticated attackers to store crafted YAML via the POST /api/1.0/symbolication endpoint. When occurrences referencing the attacker-controlled symbolication UUID are symbolicated, the stored values are passed to YAML.load with SafeYAML in unsafe mode, enabling arbitrary Ruby object deserialization and potential code execution.","categories":["Unclassified"],"product":"Squash","vendor":"Square","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-109391","source_modified_at":"2026-10-13T16:57:23.986Z","fetched_at":"2026-10-23T18:48:36.087640Z","product":"Squash","vendor":"Square","versions":[{"version":"0","lessThanOrEqual":"e73f2805f9eb30780a5c213b001f0f4255660fbf","status":"affected","versionType":"git"}],"defaultStatus":"unaffected"}],"fixed_versions":[],"cvss":9.2,"severity":"Critical","kev":{"listed":false},"epss":{"probability":0.00477,"percentile":0.40255,"score_date":"2026-10-23"},"published_at":"2026-10-12T15:16:39.257Z","modified_at":"2026-10-13T16:57:23.986Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-109391","fetched_at":"2026-10-23T18:48:36.087640Z","source_modified_at":"2026-10-13T16:57:23.986Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-109391","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://hackmd.io/@1ExmmukzRMWN7B4gQ4W-4Q/HJ87QX5ifg","tags":["technical-description","exploit"]},{"source":"CVE List","url":"https://github.com/SquareSquash/web/blob/e73f2805f9eb30780a5c213b001f0f4255660fbf/app/controllers/api/v1_controller.rb","tags":["technical-description"]},{"source":"CVE List","url":"https://github.com/SquareSquash/web/blob/e73f2805f9eb30780a5c213b001f0f4255660fbf/config/preinitializers/safe_yaml.rb","tags":["technical-description"]},{"source":"CVE List","url":"https://github.com/SquareSquash/web/blob/e73f2805f9eb30780a5c213b001f0f4255660fbf/lib/workers/symbolication_creator.rb","tags":["technical-description"]},{"source":"CVE List","url":"https://github.com/SquareSquash/web/blob/e73f2805f9eb30780a5c213b001f0f4255660fbf/app/models/symbolication.rb","tags":["technical-description"]},{"source":"CVE List","url":"https://github.com/SquareSquash/web","tags":["product"]},{"source":"CVE List","url":"https://www.vulncheck.com/advisories/square-squash-through-commit-e73f280-unauthenticated-yaml-deserialization-via-symbolication-api","tags":["third-party-advisory"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"none","automatable":"no","technical_impact":"total","assessed_at":"2026-10-13T16:40:50.798651Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":null,"confidence":"unknown","reviewed":false},"change_timestamp":"2026-10-13T16:57:23.986Z","content_hash":"5be1d62932b0d3626d19c05200bfe80f0b1f239bb5f61c3ec614880515cd1b17"}}