CVE-2021-25122

Apache Tomcat h2c request mix-up

Description

When responding to new h2c connection requests, Apache Tomcat versions 10.0.0-M1 to 10.0.0, 9.0.0.M1 to 9.0.41 and 8.5.0 to 8.5.61 could duplicate request headers and a limited amount of request body from one request to another meaning user A and user B could both see the results of user A's request.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 2.46% Top 20%
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/r7b95bc248603360501f18c8eb03bb6001ec0ee3296205b34b07105b7%40%3Cannounce.tomcat.apache.org%3E mailing list vendor advisory
https://lists.apache.org/thread.html/r7b95bc248603360501f18c8eb03bb6001ec0ee3296205b34b07105b7%40%3Cusers.tomcat.apache.org%3E mailing list
https://lists.apache.org/thread.html/r7b95bc248603360501f18c8eb03bb6001ec0ee3296205b34b07105b7%40%3Cdev.tomcat.apache.org%3E mailing list
https://lists.apache.org/thread.html/rf6d5d57b114678d8898005faef31e9fd6d7c981fcc4ccfc3bc272fc9%40%3Cdev.tomcat.apache.org%3E mailing list
https://lists.apache.org/thread.html/r7b95bc248603360501f18c8eb03bb6001ec0ee3296205b34b07105b7%40%3Cannounce.apache.org%3E mailing list
http://www.openwall.com/lists/oss-security/2021/03/01/1 third party advisory mailing list
https://lists.apache.org/thread.html/rcd90bf36b1877e1310b87ecd14ed7bbb15da52b297efd9f0e7253a3b%40%3Cusers.tomcat.apache.org%3E mailing list
https://lists.apache.org/thread.html/rd0463f9a5cbc02a485404c4b990f0da452e5ac5c237808edba11c947%40%3Cusers.tomcat.apache.org%3E mailing list
https://lists.debian.org/debian-lts-announce/2021/03/msg00018.html third party advisory mailing list
https://www.debian.org/security/2021/dsa-4891 third party advisory vendor advisory
https://www.oracle.com//security-alerts/cpujul2021.html third party advisory patch
https://security.netapp.com/advisory/ntap-20210409-0002/ third party advisory
https://www.oracle.com/security-alerts/cpuoct2021.html third party advisory patch
https://www.oracle.com/security-alerts/cpujan2022.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-2021-25122?
CVE-2021-25122 has been scored as a high severity vulnerability.
How to fix CVE-2021-25122?
To fix CVE-2021-25122, 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-2021-25122 being actively exploited in the wild?
It is possible that CVE-2021-25122 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~2% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-25122?
CVE-2021-25122 affects Apache Software Foundation Apache Tomcat.
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