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
Summary
| CVE | CVE-2026-89044 |
|---|---|
| State | PUBLISHED |
| Assigner | VulnCheck |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-09-10 18:18:16 UTC |
| Updated | 2026-09-10 19:54:25 UTC |
| 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. |
Risk And Classification
Primary CVSS: v4.0 6.9 MEDIUM from [email protected]
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
Problem Types: CWE-444 | CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 6.9 | MEDIUM | 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/C... |
| 4.0 | CNA | CVSS | 6.9 | MEDIUM | 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 |
| 3.1 | [email protected] | Primary | 6.5 | MEDIUM | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N |
| 3.1 | CNA | CVSS | 6.5 | MEDIUM | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N |
CVSS v4.0 Breakdown
Attack Vector
NetworkAttack Complexity
LowAttack Requirements
NonePrivileges Required
NoneUser Interaction
NoneConfidentiality
LowIntegrity
LowAvailability
NoneSub Conf.
NoneSub Integrity
NoneSub Availability
NoneCVSS: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
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
LowIntegrity
LowAvailability
NoneCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| github.com/netty/netty/commit/640d4d3324f7b811a4903d0730c8ccb35500500c | [email protected] | github.com | |
| github.com/netty/netty/releases/tag/netty-4.1.138.Final | [email protected] | github.com | |
| github.com/netty/netty/releases/tag/netty-4.2.18.Final | [email protected] | github.com | |
| github.com/netty/netty/blob/netty-4.1.137.Final/codec-http/src/main/java... | [email protected] | github.com | |
| github.com/netty/netty | [email protected] | github.com | |
| github.com/netty/netty/commit/ca87393b0e9e13c493d213a268e727a6d44e1585 | [email protected] | github.com | |
| github.com/netty/netty/security/advisories/GHSA-hcvj-94mj-jp5c | [email protected] | github.com | |
| www.vulncheck.com/advisories/netty-4.1.133-final-through-4.1.137-final-and-4.2.... | [email protected] | www.vulncheck.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Yu Bao, PayPal Cyber Security Team (en)
CNA: dreamlike-ocean (en)
CNA: Michael-JRead (en)
There are currently no legacy QID mappings associated with this CVE.