CVE-2026-19203

Description

A flaw was found in Jetty. A remote attacker can exploit this vulnerability by sending specially crafted HTTP/1.1 chunked requests. This can cause Jetty and an intermediary proxy to interpret different request boundaries, potentially leading to HTTP request smuggling. This issue arises from Jetty's acceptance of a lone Line Feed (LF) character as a terminator during chunked request parsing.

Statement

Jetty in affected Red Hat products may permit remote, unauthenticated HTTP request smuggling when specially crafted HTTP/1.1 chunked requests traverse an intermediary that interprets request boundaries differently. Jetty 12.1 uses RFC 9110 compliance by default and is not affected unless configured to use legacy RFC 7230 or RFC 2616 compliance modes. Remediation is being pursued for vulnerable shipped versions.

Mitigation

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score8.2N/AN/A
Attack VectorNetworkN/AN/A
Attack ComplexityLowN/AN/A
Privileges RequiredNoneN/AN/A
User InteractionNoneN/AN/A
ScopeUnchangedN/AN/A
ConfidentialityLowN/AN/A
Integrity ImpactHighN/AN/A
Availability ImpactNoneN/AN/A

Vector

Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:N

Understanding the Weakness (CWE)

Integrity,Non-Repudiation,Access Control

Technical Impact: Unexpected State; Hide Activities; Bypass Protection Mechanism

An attacker could create HTTP messages to exploit a number of weaknesses including 1) the message can trick the web server to associate a URL with another URL's webpage and caching the contents of the webpage (web cache poisoning attack), 2) the message can be structured to bypass the firewall protection mechanisms and gain unauthorized access to a web application, and 3) the message can invoke a script or a page that returns client credentials (similar to a Cross Site Scripting attack).

Frequently Asked Questions

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