CVE-2026-19203

published 2026-09-08

CVE-2026-19203: A client may issue specially crafted HTTP/1.1 chunked requests to a Jetty server that cause Jetty and an intermediary proxy to interpret different request…

Priority P3 51 high 8.3 CVSS 4.0

AV N AC L AT P PR N UI N VC L VI H 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

A client may issue specially crafted HTTP/1.1 chunked requests to a Jetty server that cause Jetty and an intermediary proxy to interpret different request boundaries, potentially resulting in HTTP request smuggling.

This is caused by Jetty accepting a lone LF character as a terminator in parts of chunked request parsing. Depending on the Jetty version and configured HTTP compliance mode, this may occur in chunk extensions, chunk data termination, or trailer termination.

Affected

5 ranges

Vendor	Product	Version range	Fixed in
eclipse_foundation	eclipse_jetty	10.0.0 – 10.0.31	—
eclipse_foundation	eclipse_jetty	11.0.0 – 11.0.31	—
eclipse_foundation	eclipse_jetty	12.0.0 – 12.0.37	—
eclipse_foundation	eclipse_jetty	12.1.0 – 12.1.11	—
eclipse_foundation	eclipse_jetty	9.4.0 – 9.4.63	—

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CWE-444