CVE-2026-89044
🔶 mediumSummary
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.
CVSS Score
6.5
Medium
EPSS Score
0.4
Exploit Probability
Published Date
2026-09-10
First Seen: 2026-09-11
📊 Relative Risk Intelligence
This CVE is Lower Risk - more severe than 46.6% of all 365,890 vulnerabilities in our database.
#195,497
Below average severity
Severity Percentile
🎯 CISA SSVC Assessment Updated: Sep 18, 2026
🔍 Exploitation Status
None
No known exploits
⚙️ Automatable
YES
Can be exploited automatically
💥 Technical Impact
Partial
Limited system impact
🏆 Discovered By
Yu Bao, PayPal Cyber Security Team
dreamlike-ocean
Michael-JRead
SSVC data provided by
CISA
Last Modified
2026-09-18
Source
NVD 🔗
CVSS Vector 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
CVSS Vector 4.0
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
CWE IDs (Weakness Types)