CVE-2026-12611

org.eclipse.jetty.http2/http2-common: org.eclipse.jetty.http2/jetty-http2-common: Jetty: Denial of Service via HTTP/2 race condition

Published Sep 8, 2026 CVSS 4.0 · 8.7 High EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Title HTTP/2 Race Condition Causing Server Denial of Service in Jetty org.eclipse.jetty.http2/http2-common: org.eclipse.jetty.http2/jetty-http2-common: Jetty: Denial of Service via HTTP/2 race condition
Weaknesses CWE-367
References
Metrics threat_severity

None

cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Important

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Title HTTP/2 Race Condition Causing Server Denial of Service in Jetty
Type Values Removed Values Added
First Time appeared Eclipse
Eclipse jetty
Vendors & Products Eclipse
Eclipse jetty
Type Values Removed Values Added
Description 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.
Weaknesses CWE-400
References
Metrics cvssV4_0

{'score': 8.7, 'vector': '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'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
eclipse
Published
Updated
Sep 9, 2026, 10:15 AM
Reserved
Jun 18, 2026, 11:34 AM
Status
Deferred
Published
Sep 8, 2026, 1:17 PM
Modified
Sep 9, 2026, 11:17 AM
Severity
Important
Public date
Sep 8, 2026, 12:28 PM