Detections
Analytics

CVE-2026-89044

medium

Description

Netty versions 4.1.133.Final through 4.1.137.Final and 4.2.13.Final through 4.2.17.Final fail to properly validate the final transfer coding in the Transfer-Encoding header, allowing attackers to smuggle requests by using malformed encoding declarations. Attackers can split Transfer-Encoding headers across multiple lines or use values like 'chunked, xchunked' to bypass validation and decode messages as chunked when the final coding is not chunked, enabling request smuggling attacks.

References

https://www.vulncheck.com/advisories/netty-4.1.133-final-through-4.1.137-final-and-4.2.13-final-through-4.2.17-final-http-request-smuggling-via-transfer-encoding

https://github.com/netty/netty/security/advisories/GHSA-hcvj-94mj-jp5c

https://github.com/netty/netty/releases/tag/netty-4.2.18.Final

https://github.com/netty/netty/releases/tag/netty-4.1.138.Final

https://github.com/netty/netty/commit/ca87393b0e9e13c493d213a268e727a6d44e1585

https://github.com/netty/netty/commit/640d4d3324f7b811a4903d0730c8ccb35500500c

https://github.com/netty/netty/blob/netty-4.1.137.Final/codec-http/src/main/java/io/netty/handler/codec/http/HttpObjectDecoder.java#L866

https://github.com/netty/netty

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-75633

Details

Source: Mitre, NVD

Published: 2026-09-10

Updated: 2026-09-18

Named Vulnerability: GHSA-77qf-r755-9gcw

Risk Information

CVSS v2

Base Score: 6.4

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:N

Severity: Medium

CVSS v3

Base Score: 6.5

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

Severity: Medium

CVSS v4

Base Score: 6.9

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

Severity: Medium

EPSS

EPSS: 0.00247