CVE-2026-12611 Race condition in Eclipse Jetty
A race condition in Jetty server allows remote attackers to cause a denial of service by blocking all server threads via specific HTTP/2 frames.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-12611?
CVE-2026-12611 is a high-severity vulnerability in Eclipse Jetty, published on 8 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-400
Which versions are affected by CVE-2026-12611?
Linux distribution packages (1)
jetty-minimal openSUSE:Tumbleweed | All versions | 9.4.58-6.1 |
How do I fix CVE-2026-12611?
Apply the vendor's patch.
Is CVE-2026-12611 being exploited?
There is no known exploitation of CVE-2026-12611 in the wild and no public exploit code.
Sources
Also known as DEBIAN-CVE-2026-12611, GHSA-gpg9-4257-cfm3, GHSA-v2pm-593h-x95w, UBUNTU-CVE-2026-12611, openSUSE-SU-2026:11804-1.