CVE-2026-42582

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 v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/netty/netty/security/advisories/GHSA-2c5c-chwr-9hqw	Exploit Vendor Advisory
https://github.com/netty/netty/security/advisories/GHSA-2c5c-chwr-9hqw	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-05-13 19:17

Updated : 2026-07-10 13:44

NVD link : CVE-2026-42582

Mitre link : CVE-2026-42582

CVE.ORG link : CVE-2026-42582

JSON object : View

Products Affected

netty

netty

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

CWE-789

Memory Allocation with Excessive Size Value

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