CVE-2021-22991

Known Exploited

Description

On BIG-IP versions 16.0.x before 16.0.1.1, 15.1.x before 15.1.2.1, 14.1.x before 14.1.4, 13.1.x before 13.1.3.6, and 12.1.x before 12.1.5.3, undisclosed requests to a virtual server may be incorrectly handled by the Traffic Management Microkernel (TMM) URI normalization, which may trigger a buffer overflow, resulting in a DoS attack. In certain situations, it may theoretically allow bypass of URL based access control or remote code execution (RCE). Note: Software versions which have reached End of Software Development (EoSD) are not evaluated.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 58.71% Top 5%
KEV Since 
Vendor Advisory f5.com
Affected: n/a BIG-IP
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-22991?
CVE-2021-22991 has been scored as a critical severity vulnerability.
How to fix CVE-2021-22991?
To fix CVE-2021-22991, 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-2021-22991 being actively exploited in the wild?
It is confirmed that CVE-2021-22991 is actively exploited. Be extra cautious if you are using vulnerable components. According to its EPSS score, there is a ~59% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-22991?
CVE-2021-22991 affects n/a BIG-IP.
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