CVE-2026-42580mediumCWE-190CWE-444

CVE-2026-42580: medium-severity vulnerability in netty

Netty: HTTP Request Smuggling due to incorrect chunk size parsing

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13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 6.5epss 0.4%
Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Netty's chunk size parser silently overflows int, enabling request smuggling attacks. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
Affected products
io.netty · netty-codec-httpnetty · netty
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