Netty: HTTP/3 QPACK literal unbounded allocation_CVE-2026-42582

7.5 / 10

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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.

Basic Information

ID CVE-2026-42582

Source GitHub_M

Published May 13, 2026 at 18:06

Modified May 13, 2026 at 19:35

Affected Product

Vendor netty

Product netty

Version >= 4.2.0.Alpha1, < 4.2.13.Final

Affected Versions netty netty >= 4.2.0.Alpha1, < 4.2.13.Final
io.netty netty-codec-http3 >= 4.2.0.Alpha1, < 4.2.13.Final

CWE Classification

CWE-770 CWE-789

References

github.com /netty/netty/security/advisories/GHSA-2c5c-chwr-9hqw

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    "published": "2026-05-13T18:06:55.559Z",
    "modified": "2026-05-13T19:35:35.549Z",
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