{"id":"CVE-2026-42582","state":"PUBLISHED","title":"Netty: HTTP/3 QPACK literal unbounded allocation","description":"Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final, when decoding header blocks, the non-Huffman branch of io.netty.handler.codec.http3.QpackDecoder#decodeHuffmanEncodedLiteral may execute new byte[length] for a string literal before verifying that length bytes are actually present in the compressed field section. The wire encoding allows a very large length to be expressed in few bytes. There is no check that length <= in.readableBytes() before new byte[length]. This vulnerability is fixed in 4.2.13.Final.","publishedAt":"2026-05-13T18:06:55.559Z","updatedAt":"2026-05-13T19:35:35.549Z","severity":{"score":7.5,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["netty netty","io.netty netty-codec-http3"],"affected":[{"vendor":"netty","product":"netty","versions":[{"version":">= 4.2.0.Alpha1, < 4.2.13.Final","status":"affected"}]},{"vendor":"io.netty","product":"netty-codec-http3","versions":[{"version":">= 4.2.0.Alpha1, < 4.2.13.Final","status":"affected"}]}],"references":["https://github.com/netty/netty/security/advisories/GHSA-2c5c-chwr-9hqw"],"weaknesses":["CWE-770","CWE-789"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/42xxx/CVE-2026-42582.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-42582","state":"PUBLISHED","datePublished":"2026-05-13T18:06:55.559Z","dateUpdated":"2026-05-13T19:35:35.549Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-04-28T17:26:12.085Z"},"containers":{"cna":{"title":"Netty: HTTP/3 QPACK literal unbounded allocation","descriptions":[{"lang":"en","value":"Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final, when decoding header blocks, the non-Huffman branch of io.netty.handler.codec.http3.QpackDecoder#decodeHuffmanEncodedLiteral may execute new byte[length] for a string literal before verifying that length bytes are actually present in the compressed field section. The wire encoding allows a very large length to be expressed in few bytes. There is no check that length <= in.readableBytes() before new byte[length]. This vulnerability is fixed in 4.2.13.Final."}],"affected":[{"vendor":"netty","product":"netty","versions":[{"version":">= 4.2.0.Alpha1, < 4.2.13.Final","status":"affected"}]},{"vendor":"io.netty","product":"netty-codec-http3","versions":[{"version":">= 4.2.0.Alpha1, < 4.2.13.Final","status":"affected"}]}],"references":[{"url":"https://github.com/netty/netty/security/advisories/GHSA-2c5c-chwr-9hqw","name":"https://github.com/netty/netty/security/advisories/GHSA-2c5c-chwr-9hqw","tags":["x_refsource_CONFIRM"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-770","lang":"en","description":"CWE-770: Allocation of Resources Without Limits or Throttling","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-789","lang":"en","description":"CWE-789: Memory Allocation with Excessive Size Value","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-05-13T18:07:22.589Z"},"source":{"advisory":"GHSA-2c5c-chwr-9hqw","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/netty/netty/security/advisories/GHSA-2c5c-chwr-9hqw","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-05-13T19:35:22.097676Z","id":"CVE-2026-42582","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-05-13T19:35:35.549Z"}}]}}}