{"id":"GHSA-4qv8-2p9j-2685","revision":"1c99ddf5449c438e8ca3a3a53519b8e9","records":[{"revision":"1c99ddf5449c438e8ca3a3a53519b8e9","observedAt":"2026-10-24T13:17:17.793+00:00","statement":{"source":"osv","id":"GHSA-4qv8-2p9j-2685","aliases":["CVE-2026-109924"],"title":"undici vulnerable to Denial of Service via unbounded memory in the EventSource parser","description":"### Impact\n\nundici's `EventSource` client can be driven to exhaust process memory by a malicious or compromised Server-Sent Events peer. By sending millions of tiny completed `data:` fields with no blank event separator, or a single unfinished line split across many chunks, the parser retains a growing amount of per-field and per-chunk state. The byte-based `maxEventSize` and `maxResponseSize` limits do not bound that retained state, and `maxResponseSize` is enforced on the compressed body before decompression, so a small compressed response can expand into enough retained memory to terminate the process. The application only needs to maintain an `EventSource` connection to an untrusted peer, which controls only the response. Availability is the only impact.\n\n### Patches\n\nUpgrade to `6.29.1`, `7.30.1`, or `8.12.2`, which bound the retained EventSource parser state (the number of `data` fields and buffered chunks, the unfinished-line length, and per-field byte totals) independently of the byte limits.\n\n### Workarounds\n\nNone.","state":0,"publishedAt":"2026-10-23T22:13:29+00:00","modifiedAt":"2026-10-23T22:30:04.1049747+00:00","affected":[{"ecosystem":"npm","name":"undici","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"6.5.0"},{"kind":"fixed","version":"6.29.1"}]}],"versions":[],"rawVersionEvidence":null},{"ecosystem":"npm","name":"undici","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"7.0.0"},{"kind":"fixed","version":"7.30.1"}]}],"versions":[],"rawVersionEvidence":null},{"ecosystem":"npm","name":"undici","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"8.0.0"},{"kind":"fixed","version":"8.12.2"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V3","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","score":null,"severity":null},{"system":"Publisher rating","vector":null,"score":null,"severity":"MODERATE"}],"references":["https://github.com/nodejs/undici/security/advisories/GHSA-4qv8-2p9j-2685","https://nvd.nist.gov/vuln/detail/CVE-2026-109924","https://github.com/nodejs/undici/commit/299162740d5f39120092277e70efacb4d151c1c6","https://github.com/nodejs/undici/commit/789ef26461c648480433846607154f52d74ec9ab","https://github.com/nodejs/undici/commit/c43b23fdc6b37e1283d4347408bb16800f867d9e","https://cna.openjsf.org/security-advisories.html","https://github.com/nodejs/undici","https://github.com/nodejs/undici/releases/tag/v6.29.1","https://github.com/nodejs/undici/releases/tag/v7.30.1","https://github.com/nodejs/undici/releases/tag/v8.12.2"],"sourceUrl":"https://github.com/advisories/GHSA-4qv8-2p9j-2685","license":"GitHub Advisory Database · CC-BY-4.0","key":"osv:GHSA-4qv8-2p9j-2685","identifiers":["GHSA-4qv8-2p9j-2685","CVE-2026-109924"]},"retained":false,"historicalAffected":[]}],"coverage":[]}