CVE-2026-12611

published 2026-09-08

CVE-2026-12611: A client may issue HTTP/2 requests to a Jetty server that result in blocking writes that are never unblocked, eventually causing all threads to be blocked and…

Priority P3 51 high 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 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 HTTP/2 requests to a Jetty server that result in blocking writes that are never unblocked, eventually causing all threads to be blocked and the whole server to become unresponsive.

This is caused by a race condition in the server when handling RST_STREAM frames and GOAWAY frames sent by the client.

The race condition "resets" the HTTP2Flusher.terminated, previously set to a non-null value, to the null value, allowing entries to be enqueued in the flusher that however will never be processed. These unprocessed entries are the ones that would unblock the write-blocked threads.

Affected

5 ranges

Vendor	Product	Version range	Fixed in
eclipse_foundation	eclipse_jetty	10.0.0 – 10.0.31	—
eclipse_foundation	eclipse_jetty	11.00 – 11.0.31	—
eclipse_foundation	eclipse_jetty	12.0.0 – 12.0.37	—
eclipse_foundation	eclipse_jetty	12.1.0 – 12.1.10	—
eclipse_foundation	eclipse_jetty	9.4.36 – 9.4.63	—

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CWE-400