CVE-2025-66560

Quarkus REST has potential worker thread starvation when HTTP connection is closed while waiting to write

Published Jan 7, 2026 CVSS 3.1 · 5.9 Medium EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-5rfx-cp42-p624 Quarkus REST has potential worker thread starvation when HTTP connection is closed while waiting to write
History
Type Values Removed Values Added
CPEs cpe:2.3:a:quarkus:quarkus:*:*:*:*:*:*:*:*
Type Values Removed Values Added
First Time appeared Quarkus
Quarkus quarkus
Vendors & Products Quarkus
Quarkus quarkus
Type Values Removed Values Added
Metrics ssvc

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

Type Values Removed Values Added
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.
Title Quarkus REST has potential worker thread starvation when HTTP connection is closed while waiting to write
Weaknesses CWE-770
References
Metrics cvssV3_1

{'score': 5.9, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Jan 7, 2026, 5:59 PM
Reserved
Dec 4, 2025, 4:01 PM
Status
Analyzed
Published
Jan 7, 2026, 6:15 PM
Modified
Oct 7, 2026, 9:10 AM
Severity
Moderate
Public date
Jan 8, 2026, 12:00 AM