CVE-2021-43980

Apache Tomcat: Information disclosure

Description

The simplified implementation of blocking reads and writes introduced in Tomcat 10 and back-ported to Tomcat 9.0.47 onwards exposed a long standing (but extremely hard to trigger) concurrency bug in Apache Tomcat 10.1.0 to 10.1.0-M12, 10.0.0-M1 to 10.0.18, 9.0.0-M1 to 9.0.60 and 8.5.0 to 8.5.77 that could cause client connections to share an Http11Processor instance resulting in responses, or part responses, to be received by the wrong client.

Category

3.7
CVSS
Severity: Low
CVSS 3.1 •
EPSS 0.17%
Vendor Advisory debian.org Vendor Advisory apache.org
Affected: Apache Software Foundation Apache Tomcat
Published at:
Updated at:

References

Link Tags
https://lists.apache.org/thread/3jjqbsp6j88b198x5rmg99b1qr8ht3g3 vendor advisory mailing list
http://www.openwall.com/lists/oss-security/2022/09/28/1 third party advisory mailing list
https://lists.debian.org/debian-lts-announce/2022/10/msg00029.html third party advisory mailing list
https://www.debian.org/security/2022/dsa-5265 third party advisory vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-43980?
CVE-2021-43980 has been scored as a low severity vulnerability.
How to fix CVE-2021-43980?
To fix CVE-2021-43980, 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-2021-43980 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-43980 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-43980?
CVE-2021-43980 affects Apache Software Foundation Apache Tomcat.
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