Uncontrolled Memory Allocation in Jetty - CVE-2026-19204
Published: September 16, 2026
Vulnerability identifier: #VU150236
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-19204
CWE-ID: CWE-789
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to memory allocation with an excessive size value in the Jetty WebSocket frame parser\'s Parser.parsePayload method when processing a WebSocket frame with a reserved opcode and an oversized declared payload length. A remote attacker can send a specially crafted WebSocket frame header to cause a denial of service.
Auto-fragmentation is enabled by default, and reserved opcodes bypass the applicable frame-size checks before opcode validation occurs.
Affected software
Jetty
How to mitigate CVE-2026-19204
Install security update from vendor's website.
Jetty - addressed in versions 10.0.32, 11.0.32, 12.0.38, 12.1.12