{"items":[{"id":"NVI-00015217","kind":"vulnerability","title":"undici vulnerable to CRLF Injection via blob-like body 'type' property","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-m8rv-5g2x-5cg5","CVE-2026-15157"],"plain_summary":"GitHub lists this reviewed advisory for undici, undici, undici. 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-429bc07311f2dd9914d32aa1df16ab4e"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-08-03T19:33:56.000Z","value":"4.2 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-429bc07311f2dd9914d32aa1df16ab4e"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-429bc07311f2dd9914d32aa1df16ab4e","url":"https://github.com/advisories/GHSA-m8rv-5g2x-5cg5","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-m8rv-5g2x-5cg5","publisher":"GitHub Advisory Database","observed_at":"2026-11-03T09:58:33.950Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-429bc07311f2dd9914d32aa1df16ab4e"],"technology":"undici","known_exclusions":[],"conditions_summary":"### Impact\n\nWhen an application passes a duck-typed blob-like body to undici's HTTP/1.1 dispatcher (via `request()`, `stream()`, `pipeline()`, or `dispatch()`) with a `.type` derived from untrusted input, an attacker can inject CRLF sequences (`\\r\\n`) to append arbitrary HTTP headers and potentially smuggle a second request past the upstream.\n\nThe vulnerable branch in `lib/dispatcher/client-h1.js` pushes `body.type` directly into the outgoing headers with no validation, while every other header path in undici goes through `isValidHeaderValue()`:\n\n```javascript\n} else if (util.isBlobLike(body) && request.contentType == null && body.type) {\n  headers.push('content-type', body.type)  // bypasses isValidHeaderValue()\n}\n```\n\nThe bug requires a hand-rolled duck-typed blob object or a Blob subclass with a controlled `.type`. Native `Blob` is safe because its constructor strips CRLF from `.type`. `fetch()` is unaffected because it validates via the `Headers` class. Ecosystem consumers that build duck-typed blob shapes from user input include `form-data-encoder`, `formdata-polyfill`, and `formdata-node`.\n\nSame defect class as `CVE-2022-35948` (explicit `content-type` sink, fixed in undici 5","public_affected_ranges":["< 6.28.0"]},{"certainty":"source_listed","source_ids":["sr-429bc07311f2dd9914d32aa1df16ab4e"],"technology":"undici","known_exclusions":[],"conditions_summary":"### Impact\n\nWhen an application passes a duck-typed blob-like body to undici's HTTP/1.1 dispatcher (via `request()`, `stream()`, `pipeline()`, or `dispatch()`) with a `.type` derived from untrusted input, an attacker can inject CRLF sequences (`\\r\\n`) to append arbitrary HTTP headers and potentially smuggle a second request past the upstream.\n\nThe vulnerable branch in `lib/dispatcher/client-h1.js` pushes `body.type` directly into the outgoing headers with no validation, while every other header path in undici goes through `isValidHeaderValue()`:\n\n```javascript\n} else if (util.isBlobLike(body) && request.contentType == null && body.type) {\n  headers.push('content-type', body.type)  // bypasses isValidHeaderValue()\n}\n```\n\nThe bug requires a hand-rolled duck-typed blob object or a Blob subclass with a controlled `.type`. Native `Blob` is safe because its constructor strips CRLF from `.type`. `fetch()` is unaffected because it validates via the `Headers` class. Ecosystem consumers that build duck-typed blob shapes from user input include `form-data-encoder`, `formdata-polyfill`, and `formdata-node`.\n\nSame defect class as `CVE-2022-35948` (explicit `content-type` sink, fixed in undici 5","public_affected_ranges":[">= 7.0.0, < 7.29.0"]},{"certainty":"source_listed","source_ids":["sr-429bc07311f2dd9914d32aa1df16ab4e"],"technology":"undici","known_exclusions":[],"conditions_summary":"### Impact\n\nWhen an application passes a duck-typed blob-like body to undici's HTTP/1.1 dispatcher (via `request()`, `stream()`, `pipeline()`, or `dispatch()`) with a `.type` derived from untrusted input, an attacker can inject CRLF sequences (`\\r\\n`) to append arbitrary HTTP headers and potentially smuggle a second request past the upstream.\n\nThe vulnerable branch in `lib/dispatcher/client-h1.js` pushes `body.type` directly into the outgoing headers with no validation, while every other header path in undici goes through `isValidHeaderValue()`:\n\n```javascript\n} else if (util.isBlobLike(body) && request.contentType == null && body.type) {\n  headers.push('content-type', body.type)  // bypasses isValidHeaderValue()\n}\n```\n\nThe bug requires a hand-rolled duck-typed blob object or a Blob subclass with a controlled `.type`. Native `Blob` is safe because its constructor strips CRLF from `.type`. `fetch()` is unaffected because it validates via the `Headers` class. Ecosystem consumers that build duck-typed blob shapes from user input include `form-data-encoder`, `formdata-polyfill`, and `formdata-node`.\n\nSame defect class as `CVE-2022-35948` (explicit `content-type` sink, fixed in undici 5","public_affected_ranges":[">= 8.0.0, < 8.9.0"]}],"null_published_at":"2026-11-03T10:03:26.562Z","source_updated_at":"2026-08-03T19:33:56.000Z","source_disclosed_at":"2026-08-03T19:33:53.000Z","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":"2026-11-03T09:58:33.950Z"}],"next_cursor":null,"snapshot_revision":"42594"}