CVE-2021-42340

HighCVSS 7.5/10Last modified Jun 17, 2026

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.

Metrics

CVSS 3.1 7.5/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness enumeration

CWE-772

Affected software

VendorProductVersions
Apache Software FoundationApache TomcatApache 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

References

Timeline

Published
Oct 14, 2021
Last modified
Jun 17, 2026
NVD status
Modified

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CVE-2021-42340: High severity, CVSS 7.5 | Vulnix