CVE-2026-89044

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.28% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 20.7% of scored records. A rank, not a probability.

NVD base score

6.9 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

NVD analysis status

Analyzed. NVD last modified this record on 2026-09-18.

Red Hat severity

Moderate. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-09-10 17:39Z1 MO AGO

Last updated

2026-09-18 17:23Z1 MO AGO

Reserved

2026-09-10

Assigning CNA

VulnCheck

Record state

PUBLISHED

Severity

Medium (CVSS 6.9)

CNA CVSS 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

Weaknesses

• CWE-444Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')Base

Data version

5.2

Document digest

8793a2dcb781b5e15895ec0c07830a2795dffe4417025b438210982ad53b0a66

• github.comGitHub Security Advisory (GHSA-hcvj-94mj-jp5c)https://github.com/netty/netty/security/advisories/GHSA-hcvj-94mj-jp5cvendor-advisory
• github.comFix commit on the 4.1 branch: match the final transfer-coding token exactlyhttps://github.com/netty/netty/commit/ca87393b0e9e13c493d213a268e727a6d44e1585patch
• github.comFix commit on the 4.2 branchhttps://github.com/netty/netty/commit/640d4d3324f7b811a4903d0730c8ccb35500500cpatch
• github.comSuffix-based chunked-must-be-last check at netty-4.1.137.Finalhttps://github.com/netty/netty/blob/netty-4.1.137.Final/codec-http/src/main/java/io/netty/handler/codec/http/HttpObjectDecoder.java#L866technical-description
• github.comnetty netty-4.1.138.Final Release Noteshttps://github.com/netty/netty/releases/tag/netty-4.1.138.Finalrelease-notes
• github.comnetty netty-4.2.18.Final Release Noteshttps://github.com/netty/netty/releases/tag/netty-4.2.18.Finalrelease-notes
• github.comnetty/nettyhttps://github.com/netty/nettyproduct
• www.vulncheck.comVulnCheck Advisory: 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-Encodinghttps://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-encodingthird-party-advisory