{"id":"CVE-2026-43967","aliases":["EEF-CVE-2026-43967","GHSA-9mhv-8h52-q7q2"],"url":"https://o3.security/vulnerability/CVE-2026-43967","summary":"Quadratic fragment-name uniqueness check causes denial of service in absinthe","details":"Inefficient Algorithmic Complexity vulnerability in absinthe-graphql absinthe allows unauthenticated denial of service via quadratic fragment-name uniqueness validation.\n\n'Elixir.Absinthe.Phase.Document.Validation.UniqueFragmentNames':run/2 iterates over all fragments and for each one calls duplicate?/2, which evaluates Enum.count(fragments, &(&1.name == name)) — a full linear scan of the fragment list. The result is O(N²) comparisons per document, where N is the number of fragment definitions supplied by the caller.\n\nBecause input.fragments is built directly from the GraphQL query body, N is fully attacker-controlled. A minimum-size fragment definition is roughly 16 bytes, so a ~1 MB document carries ~60,000 fragments and forces ~3.6 × 10⁹ comparisons inside this single validation phase. No authentication, schema knowledge, or special configuration is required.\n\nThis issue affects absinthe: from 1.2.0 before 1.10.2.","published":"2026-05-08T15:42:34.347Z","modified":"2026-07-15T01:49:01.476104743Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Hex","name":"absinthe","fixedVersion":"1.10.2"}],"fix":{"url":"https://github.com/absinthe-graphql/absinthe/commit/223600c520493dcaf95080af552c413099f92c9d","label":"absinthe-graphql/absinthe@223600c"},"references":[{"type":"WEB","url":"https://cna.erlef.org/cves/CVE-2026-43967.html"},{"type":"WEB","url":"https://github.com"},{"type":"WEB","url":"https://osv.dev/vulnerability/EEF-CVE-2026-43967"},{"type":"WEB","url":"https://repo.hex.pm"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43967.json"},{"type":"ADVISORY","url":"https://github.com/absinthe-graphql/absinthe/security/advisories/GHSA-9mhv-8h52-q7q2"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-43967"},{"type":"FIX","url":"https://github.com/absinthe-graphql/absinthe/commit/223600c520493dcaf95080af552c413099f92c9d"},{"type":"PACKAGE","url":"https://github.com/absinthe-graphql/absinthe"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-07-15T01:49:01.476104743Z"}}