Live › vulnerability › CVE-2021-22991
Go to dashboardF5 BIG-IP's Traffic Management Microkernel has a buffer overflow that lets a remote attacker bypass URL-based access controls. CISA lists it as actively exploited in the wild.
Summary written from the sources below. Check the originals before acting.
First seen by InfraStack 2026-10-23 19:11 UTC, 3h before NVD. All times on this page are UTC.
Apply updates per vendor instructions.
| Product | Ecosystem | Affected | Fixed in |
|---|---|---|---|
| F5 BIG-IP Traffic Management Microkernel | vendor | – | – |
Unknown from the sources.
Apply the F5 BIG-IP update per the vendor advisory (the sources do not name the fixed version).
Each row is the first time that source carried this signal. The analyst’s rows are its own findings.
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.
This page as .md · .json · in your agent: get_signal("CVE-2021-22991")
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