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 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.
What this means for your business
- FIRST's prediction model gives it a 0.3% chance of attack attempts being seen in the next 30 days, ranking above 16% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- Not yet scored
- CVSS v4
- 8.7
- Weakness
- CWE-400
- Assigned by
- emo@eclipse.org
Dates
- Published
- 2026-09-08
- Last modified
- 2026-09-09
- Sources
- NVD