Vulnerability · Published Jan 7, 2026 · Assigned by GitHub_M
CVE-2025-66560Quarkus REST has potential worker thread starvation when HTTP connection is closed while waiting to write
Medium 5.9
In plain English
A medium-severity resource allocation without limits in quarkus from quarkusio. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 32% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Quarkus is a Cloud Native, (Linux) Container First framework for writing Java applications. Prior to versions 3.31.0, 3.27.2, and 3.20.5, a vulnerability exists in the HTTP layer of Quarkus REST related to response handling. When a response is being written, the framework waits for previously written response chunks to be fully transmitted before proceeding. If the client connection is dropped during this waiting period, the associated worker thread is never released and becomes permanently blocked. Under sustained or repeated occurrences, this can exhaust the available worker threads, leading to degraded performance, or complete unavailability of the application. This issue has been patched in versions 3.31.0, 3.27.2, and 3.20.5. A workaround involves implementing a health check that monitors the status and saturation of the worker thread pool to detect abnormal thread retention early.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Maven | io.quarkus:quarkus-rest | 3.20.5 | GHSA-5rfx-cp42-p624 |
| Maven | io.quarkus:quarkus-rest | 3.27.2 | GHSA-5rfx-cp42-p624 |
| Maven | io.quarkus:quarkus-rest | 3.31.0 | GHSA-5rfx-cp42-p624 |
Affected products (as reported)
Weakness: CWE-770 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- https://github.com/quarkusio/quarkus/security/advisories/GHSA-5rfx-cp42-p624 x_refsource_CONFIRM