CVE-2021-42340

DoS via memory leak with WebSocket connections

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.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 2.97% Top 15%
Vendor Advisory debian.org Vendor Advisory gentoo.org Vendor Advisory apache.org
Affected: Apache Software Foundation Apache Tomcat
Published at:
Updated at:

References

Link Tags
https://lists.apache.org/thread.html/r83a35be60f06aca2065f188ee542b9099695d57ced2e70e0885f905c%40%3Cannounce.tomcat.apache.org%3E vendor advisory mailing list
https://lists.apache.org/thread.html/r8097a2d1550aa78e585fc77e602b9046e6d4099d8d132497c5387784%40%3Ccommits.myfaces.apache.org%3E mailing list
https://www.debian.org/security/2021/dsa-5009 third party advisory vendor advisory
https://www.oracle.com/security-alerts/cpujan2022.html third party advisory patch
https://security.netapp.com/advisory/ntap-20211104-0001/ third party advisory
https://kc.mcafee.com/corporate/index?page=content&id=SB10379 third party advisory
https://www.oracle.com/security-alerts/cpuapr2022.html third party advisory patch
https://www.oracle.com/security-alerts/cpujul2022.html third party advisory patch
https://security.gentoo.org/glsa/202208-34 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-42340?
CVE-2021-42340 has been scored as a high severity vulnerability.
How to fix CVE-2021-42340?
To fix CVE-2021-42340, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-42340 being actively exploited in the wild?
It is possible that CVE-2021-42340 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~3% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-42340?
CVE-2021-42340 affects Apache Software Foundation Apache Tomcat.
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