CVE-2021-42340 - CVE House
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Status published High CVE-2021-42340

DoS via memory leak with WebSocket connections

Vulnerability Description

The fix for bug 63362 present in Apache Tomcat 10.1.0-M1 to 10.1.0-M5, 10.0.0-M1 to 10.0.11, 9.0.40 to 9.0.53 and 8.5.60 to 8.5.71 introduced a memory leak. The object introduced to collect metrics for HTTP upgrade connections was not released for WebSocket connections once the connection was closed. This created a memory leak that, over time, could lead to a denial of service via an OutOfMemoryError.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

Affected Vendor

Apache Software Foundation

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Affected Software

Apache Tomcat
Vulnerable Versions:
Apache Tomcat 10 10.0.0-M10 to 10.0.11, Apache Tomcat 10 10.1.0-M1 to 10.1.0-M5, Apache Tomcat 9 9.0.40 to 9.0.53, Apache Tomcat 8 8.5.60 to 8.5.71

Timeline

Official Publish: October 14th, 2021
Last Modified: August 4th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weaknesses (CWE)

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.