{"schema":"threatline.record/2","record":{"id":"CVE-2026-85008","aliases":["GHSA-8436-99hf-9mmv"],"summary":"undici vulnerable to caching and replay of unsafe HTTP method responses","details":"### Impact\n\nundici's `interceptors.cache()` documents that it caches only safe HTTP methods. However, its internal skip-list is built by subtracting the configured methods from the safe-methods set, so an unsafe method (`POST`, `PUT`, `PATCH`, `DELETE`) never lands in the skip-list and is looked up against the cache store. Combined with the storage gate (`canCacheResponse`) having no method check, a heuristically-cacheable response (for example a `404`) with an explicit `Cache-Control: max-age=...` to an unsafe method is stored and replayed on a subsequent identical request. The application's state-changing request never reaches the origin, and undici serves a fabricated response from the cache instead. This occurs with the default configuration (`methods: ['GET']`), which the public API does not allow widening to unsafe methods, so no application misuse is required; an untrusted origin can trigger it purely through its own response headers.\n\n### Patches\n\nUpgrade to `7.29.1` or `8.10.2`. The cache interceptor no longer reads from or writes to the cache for unsafe HTTP methods, while still invalidating existing cache entries on successful unsafe requests.\n\n### Workarounds\n\nNone.","categories":["Libraries & packages"],"product":"undici","vendor":"undici","ecosystem":"npm","affected_ranges":[{"source":"GitHub Advisory Database","source_url":"https://github.com/advisories/GHSA-8436-99hf-9mmv","source_modified_at":"2026-09-29T18:16:29Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"npm","name":"undici"},"range":">= 7.0.0, < 7.29.1"},{"source":"GitHub Advisory Database","source_url":"https://github.com/advisories/GHSA-8436-99hf-9mmv","source_modified_at":"2026-09-29T18:16:29Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"npm","name":"undici"},"range":">= 8.0.0, < 8.10.2"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-85008","source_modified_at":"2026-09-04T19:28:57.123Z","fetched_at":"2026-10-23T18:45:31.882637Z","product":"undici","vendor":"undici","versions":[{"versionType":"semver","status":"affected","version":"7.0.0","lessThan":"7.29.1"},{"versionType":"semver","status":"unaffected","version":"7.29.1"},{"versionType":"semver","status":"affected","version":"8.0.0","lessThan":"8.10.2"},{"versionType":"semver","status":"unaffected","version":"8.10.2"}],"defaultStatus":"unaffected"},{"source":"OSV","source_url":"https://osv.dev/vulnerability/GHSA-8436-99hf-9mmv","source_modified_at":"2026-09-29T18:28:12.530229215Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"npm","name":"undici","purl":"pkg:npm/undici"},"ranges":[{"events":[{"introduced":"7.0.0"},{"fixed":"7.29.1"}],"type":"SEMVER"}],"versions":[]},{"source":"OSV","source_url":"https://osv.dev/vulnerability/GHSA-8436-99hf-9mmv","source_modified_at":"2026-09-29T18:28:12.530229215Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"npm","name":"undici","purl":"pkg:npm/undici"},"ranges":[{"events":[{"introduced":"8.0.0"},{"fixed":"8.10.2"}],"type":"SEMVER"}],"versions":[]}],"fixed_versions":[{"source":"GitHub Advisory Database","source_url":"https://github.com/advisories/GHSA-8436-99hf-9mmv","source_modified_at":"2026-09-29T18:16:29Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"npm","name":"undici"},"version":"7.29.1"},{"source":"GitHub Advisory Database","source_url":"https://github.com/advisories/GHSA-8436-99hf-9mmv","source_modified_at":"2026-09-29T18:16:29Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"npm","name":"undici"},"version":"8.10.2"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-85008","source_modified_at":"2026-09-04T19:28:57.123Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"undici","ecosystem":null},"version":"7.29.1","basis":"first unaffected version stated in the CVE record"},{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-85008","source_modified_at":"2026-09-04T19:28:57.123Z","fetched_at":"2026-10-23T18:45:31.882637Z","package":{"name":"undici","ecosystem":null},"version":"8.10.2","basis":"first unaffected version stated in the CVE record"},{"source":"OSV","source_url":"https://osv.dev/vulnerability/GHSA-8436-99hf-9mmv","source_modified_at":"2026-09-29T18:28:12.530229215Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"npm","name":"undici","purl":"pkg:npm/undici"},"version":"7.29.1"},{"source":"OSV","source_url":"https://osv.dev/vulnerability/GHSA-8436-99hf-9mmv","source_modified_at":"2026-09-29T18:28:12.530229215Z","fetched_at":"2026-10-23T18:42:43.628194Z","package":{"ecosystem":"npm","name":"undici","purl":"pkg:npm/undici"},"version":"8.10.2"}],"cvss":3.7,"severity":"Low","kev":{"listed":false},"epss":{"probability":0.00118,"percentile":0.01615,"score_date":"2026-10-23"},"published_at":"2026-09-04T16:42:40.780Z","modified_at":"2026-09-29T18:28:12.530229215Z","provenance":[{"source":"GitHub Advisory Database","url":"https://github.com/advisories/GHSA-8436-99hf-9mmv","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-09-29T18:16:29Z"},{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-85008","fetched_at":"2026-10-23T18:45:31.882637Z","source_modified_at":"2026-09-04T19:28:57.123Z"},{"source":"OSV","url":"https://osv.dev/vulnerability/GHSA-8436-99hf-9mmv","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-09-29T18:28:12.530229215Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-85008","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["GitHub Advisory Database","CVE List","OSV","EPSS"],"references":[{"source":"CVE List","url":"https://github.com/nodejs/undici/security/advisories/GHSA-8436-99hf-9mmv"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-85008","source":"GitHub Advisory Database"},{"url":"https://github.com/nodejs/undici/commit/2be07bf97b3022e0324142d31f99f6e019d815e3","source":"GitHub Advisory Database"},{"url":"https://github.com/nodejs/undici/commit/b61d9432bac7caac51273ad209862e4c0bf935ae","source":"GitHub Advisory Database"},{"source":"CVE List","url":"https://cna.openjsf.org/security-advisories.html"},{"url":"https://github.com/nodejs/undici/releases/tag/v7.29.1","source":"GitHub Advisory Database"},{"url":"https://github.com/nodejs/undici/releases/tag/v8.10.2","source":"GitHub Advisory Database"},{"url":"https://github.com/advisories/GHSA-8436-99hf-9mmv","source":"GitHub Advisory Database"}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","ssvc":{"exploitation":"none","automatable":"no","technical_impact":"partial","assessed_at":"2026-09-04T19:28:49.240361Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"ecosystem","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-09-29T18:28:12.530229215Z","content_hash":"f54dbd6e46ed04bbe39df6c8b25af4ed133f8d7f89a07fba2a49df6b885a8ddd"}}