{"cve":"CVE-2026-42582","nvd":{"published":"2026-05-13T19:17:23.763","modified":"2026-10-26T00:10:00.150","status":"Analyzed","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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-770","CWE-789"],"references":["https://github.com/netty/netty/security/advisories/GHSA-2c5c-chwr-9hqw","https://github.com/netty/netty/security/advisories/GHSA-2c5c-chwr-9hqw"],"products":["netty:netty"],"source":"nvd","synced_at":"2026-10-26T00:31:35.753532240+00:00"},"epss":{"cve":"CVE-2026-42582","score":0.00437,"percentile":0.3769,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-2c5c-chwr-9hqw","url":"https://osv.dev/vulnerability/GHSA-2c5c-chwr-9hqw","summary":"Netty HTTP/3 QPACK literal unbounded allocation","modified":"2026-09-10T03:50:45.231064445Z","packages":[{"ecosystem":"Maven","name":"io.netty:netty-codec-http3","purl":"pkg:maven/io.netty/netty-codec-http3","ranges":[">=4.2.0.Final <4.2.13.Final"],"fixed":["4.2.13.Final"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}