{"schemaVersion":3,"id":"CVE-2026-109924","aliases":["DEBIAN-CVE-2026-109924","UBUNTU-CVE-2026-109924"],"status":"published","duplicateOf":null,"title":null,"description":"undici is an HTTP client library for Node.js. In versions 6.5.0 through 6.29.0, 7.0.0 through 7.30.0, and 8.0.0 through 8.12.1, its 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 that the byte-based maxEventSize and maxResponseSize limits do not bound, and because maxResponseSize is enforced on the compressed body before decompression, a small compressed response can expand into enough retained memory to terminate the process. An application only needs to maintain an EventSource connection to an untrusted peer, which controls only the response, and availability is the only impact. The issue is fixed in undici 6.29.1, 7.30.1, and 8.12.2, which bound the retained parser state independently of the byte limits, and users should upgrade to one of those versions or later. There is no workaround.","dates":{"published":"2026-10-15T18:16:48.452Z","modified":"2026-10-16T20:05:22.386Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":7.5,"severity":"high","version":"3.1","versionLabel":"v3.1","source":"NVD","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":5.9,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":7.5,"severity":"high","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"OSV · Debian","score":5.9,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","exploitability":5.6,"impact":6,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"OSV · 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of Resources Without Limits or Throttling","description":"The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.","type":"weakness","status":"Incomplete","abstraction":"Base","likelihoodOfExploit":"High","url":"https://cwe.mitre.org/data/definitions/770.html"}],"affected":[{"vendor":"debian","product":"node-undici","name":"node-undici","label":"node-undici","ecosystem":"Debian","cpePart":null,"purl":"pkg:deb/debian/node-undici","purlType":"deb","versions":[{"text":"All versions","noFixRecorded":true,"fixedIn":null}],"versionsText":"All versions (No fix recorded)","eol":null,"hubHref":null},{"vendor":"ubuntu","product":"node-undici","name":"node-undici","label":"node-undici","ecosystem":"Ubuntu","cpePart":null,"purl":"pkg:deb/ubuntu/node-undici","purlType":"deb","versions":[{"text":"All versions","noFixRecorded":true,"fixedIn":null}],"versionsText":"All versions (No fix recorded)","eol":null,"hubHref":null},{"vendor":"nodejs","product":"undici","name":"undici","label":"undici","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"≥ 6.5.0, < 6.29.1","noFixRecorded":false,"fixedIn":null},{"text":"≥ 7.0.0, < 7.30.1","noFixRecorded":false,"fixedIn":null},{"text":"≥ 8.0.0, < 8.12.2","noFixRecorded":false,"fixedIn":null}],"versionsText":"≥ 6.5.0, < 6.29.1 | ≥ 7.0.0, < 7.30.1 | ≥ 8.0.0, < 8.12.2","eol":null,"hubHref":"/vendor/nodejs/undici"},{"vendor":"undici","product":"undici","name":"undici","label":"undici","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"≥ 6.5.0, < 6.29.1","noFixRecorded":false,"fixedIn":null},{"text":"≥ 7.0.0, < 7.30.1","noFixRecorded":false,"fixedIn":null},{"text":"≥ 8.0.0, < 8.12.2","noFixRecorded":false,"fixedIn":null}],"versionsText":"≥ 6.5.0, < 6.29.1 | ≥ 7.0.0, < 7.30.1 | ≥ 8.0.0, < 8.12.2","eol":null,"hubHref":"/vendor/undici/undici"}],"affectedCount":4,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://github.com/nodejs/undici/security/advisories/GHSA-4qv8-2p9j-2685","label":"github.com/nodejs/undici/security/advisories/GHSA-4qv8-2p9j-2685","hostname":"github.com","tags":["REPORT","Vendor Advisory"]},{"url":"https://cna.openjsf.org/security-advisories.html","label":"cna.openjsf.org/security-advisories.html","hostname":"cna.openjsf.org","tags":["REPORT","Vendor Advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-109924","label":"security-tracker.debian.org/tracker/CVE-2026-109924","hostname":"security-tracker.debian.org","tags":["Advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-109924","label":"ubuntu.com/security/CVE-2026-109924","hostname":"ubuntu.com","tags":["REPORT"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-109924","label":"www.cve.org/CVERecord?id=CVE-2026-109924","hostname":"www.cve.org","tags":["REPORT"]}],"lineage":{"upstream":[],"downstream":[],"duplicates":[],"related":[]},"timeline":[{"kind":"published","date":"2026-10-15T18:16:48.452Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2026-10-16T20:05:22.386Z","label":"Last modified","detail":"Vulnerability information 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