Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
This is the Maven package io.netty:netty-codec-http, affected in versions from 4.2.0.Alpha1 before 4.2.13.Final and in versions before 4.1.133.Final. Netty treats a request with "Transfer-Encoding: chunked, identity" as chunked, which violates RFC 9112 and can allow request smuggling when Netty sits behind a proxy that prefers Content-Length. An attacker able to send requests through such a proxy can inject additional HTTP requests. Upgrade to 4.2.13.Final or 4.1.133.Final.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 6.5 | Medium | 3.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0027, the 18th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:16 UTC First seen by agentprime
- 31 Oct 2026, 14:16 UTC Confirmed by OSV