Uncontrolled Memory Allocation in Netty - CVE-2026-42582
Published: May 5, 2026
Vulnerability identifier: #VU130207
CSH Severity: Medium
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-42582
CWE-ID: CWE-789
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
Netty
Netty
Software vendor:
Netty project
Netty project
Description
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to memory allocation with excessive size value in io.netty.handler.codec.http3.QpackDecoder#decodeHuffmanEncodedLiteral when decoding HTTP/3 QPACK literal header fields. A remote attacker can send a specially crafted HTTP/3 HEADERS frame to cause a denial of service.
The issue occurs in the non-Huffman decoding branch before the claimed literal length is verified against the available bytes in the compressed field section.
Remediation
Install security update from vendor's website.