{"items":[{"id":"NVI-00010703","kind":"vulnerability","title":"fastify is vulnerable to header validation bypass via case-sensitive propertyNames","revision":5,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected.","NVD lastModified does not establish freshness of every associated CPE record."],"lifecycle":"active","identifiers":["GHSA-389g-gv7q-r4x8","CVE-2026-107832"],"plain_summary":"GitHub lists this reviewed advisory for fastify. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-1bd706a3f6b07f3fdb3b6c9ae794c084"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. 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The same rule written in lowercase works, and the `not: { required: [...] }` form is unaffected, so this is a gap in the built-in normalization rather than a wrong schema. This is an incomplete fix of CVE-2026-84428 (GHSA-9q9j-q6p8-xq58), whose normalization covered header names used as property keys but not those used as values inside `propertyNames`.\n\n### Patches\n\nUsers should upgrade to fastify `5.12.6` or later, which lowercases header names held in `enum` and `const` inside a `propertyNa","public_affected_ranges":[">= 5.12.2, < 5.12.6"]},{"certainty":"source_listed","source_ids":["sr-f4c4317ac20d050077b2823d7cf93ee1"],"technology":"fastify","known_exclusions":[],"conditions_summary":"### Impact\n\nFastify lowercases header names in a `headers` schema before compilation, because Node.js stores request header names in lowercase. This normalization does not reach the header names held in a `propertyNames` subschema's `enum` and `const`. 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The same rule written in lowercase works, and the `not: { required: [...] }` form is unaffected, so this is a gap in the built-in normalization rather than a wrong schema. This is an incomplete fix of CVE-2026-84428 (GHSA-9q9j-q6p8-xq58), whose normalization covered header names used as property keys but not those used as values inside `propertyNames`.\n\n### Patches\n\nUsers should upgrade to fastify `5.12.6` or later, which lowercases header names held in `enum` and `const` inside a `propertyNa","public_affected_ranges":[">= 5.12.2, < 5.12.6"]},{"certainty":"source_listed","source_ids":["sr-f4c4317ac20d050077b2823d7cf93ee1"],"technology":"fastify","known_exclusions":[],"conditions_summary":"### Impact\n\nFastify lowercases header names in a `headers` schema before compilation, because Node.js stores request header names in lowercase. This normalization does not reach the header names held in a `propertyNames` subschema's `enum` and `const`. A header-name deny-list written in the canonical header case, such as `propertyNames: { not: { enum: ['X-Debug-Override'] } }`, therefore never matches the lowercased request headers, and the forbidden header reaches the handler. Any application that uses a `propertyNames` deny-list or allow-list to constrain request header names does not get the constraint it expects. The same rule written in lowercase works, and the `not: { required: [...] }` form is unaffected, so this is a gap in the built-in normalization rather than a wrong schema. This is an incomplete fix of CVE-2026-84428 (GHSA-9q9j-q6p8-xq58), whose normalization covered header names used as property keys but not those used as values inside `propertyNames`.\n\n### Patches\n\nUsers should upgrade to fastify `5.12.6` or later, which lowercases header names held in `enum` and `const` inside a `propertyNa","public_affected_ranges":["SEMVER: introduced 5.12.2; fixed 5.12.6"]}],"null_published_at":"2026-11-07T00:57:04.328Z","source_updated_at":"2026-10-22T16:40:37.000Z","source_disclosed_at":"2026-10-22T16:40:35.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Source facts changed; compare the preserved prior revision.","null_first_observed_at":"2026-10-31T22:07:30.906Z"},{"id":"NVI-00010703","kind":"vulnerability","title":"fastify is vulnerable to header validation bypass via case-sensitive propertyNames","revision":3,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected.","NVD lastModified does not establish freshness of every associated CPE record."],"lifecycle":"active","identifiers":["GHSA-389g-gv7q-r4x8","CVE-2026-107832"],"plain_summary":"GitHub lists this reviewed advisory for fastify. 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The same rule written in lowercase works, and the `not: { required: [...] }` form is unaffected, so this is a gap in the built-in normalization rather than a wrong schema. 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A header-name deny-list written in the canonical header case, such as `propertyNames: { not: { enum: ['X-Debug-Override'] } }`, therefore never matches the lowercased request headers, and the forbidden header reaches the handler. Any application that uses a `propertyNames` deny-list or allow-list to constrain request header names does not get the constraint it expects. The same rule written in lowercase works, and the `not: { required: [...] }` form is unaffected, so this is a gap in the built-in normalization rather than a wrong schema. This is an incomplete fix of CVE-2026-84428 (GHSA-9q9j-q6p8-xq58), whose normalization covered header names used as property keys but not those used as values inside `propertyNames`.\n\n### Patches\n\nUsers should upgrade to fastify `5.12.6` or later, which lowercases header names held in `enum` and `const` inside a `propertyNa","public_affected_ranges":[">= 5.12.2, < 5.12.6"]}],"null_published_at":"2026-10-31T23:18:22.439Z","source_updated_at":"2026-10-22T16:40:37.000Z","source_disclosed_at":"2026-10-22T16:40:35.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.","null_first_observed_at":"2026-10-31T22:07:30.906Z"},{"id":"NVI-00010703","kind":"vulnerability","title":"fastify is vulnerable to header validation bypass via case-sensitive propertyNames","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-389g-gv7q-r4x8","CVE-2026-107832"],"plain_summary":"GitHub lists this reviewed advisory for fastify. 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A header-name deny-list written in the canonical header case, such as `propertyNames: { not: { enum: ['X-Debug-Override'] } }`, therefore never matches the lowercased request headers, and the forbidden header reaches the handler. Any application that uses a `propertyNames` deny-list or allow-list to constrain request header names does not get the constraint it expects. The same rule written in lowercase works, and the `not: { required: [...] }` form is unaffected, so this is a gap in the built-in normalization rather than a wrong schema. This is an incomplete fix of CVE-2026-84428 (GHSA-9q9j-q6p8-xq58), whose normalization covered header names used as property keys but not those used as values inside `propertyNames`.\n\n### Patches\n\nUsers should upgrade to fastify `5.12.6` or later, which lowercases header names held in `enum` and `const` inside a `propertyNa","public_affected_ranges":[">= 5.12.2, < 5.12.6"]}],"null_published_at":"2026-10-31T22:27:12.376Z","source_updated_at":"2026-10-22T16:40:37.000Z","source_disclosed_at":"2026-10-22T16:40:35.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"First indexed by Null; source disclosure date is shown separately.","null_first_observed_at":"2026-10-31T22:07:30.906Z"}],"next_cursor":null,"snapshot_revision":"42594"}