CVE-2021-22977 Denial of service in BIG-IP

What is CVE-2021-22977?

CVE-2021-22977 is a high-severity denial of service vulnerability in F5 Big-Ip Access Policy Manager, published on 12 Feb 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

On BIG-IP version 16.0.0-16.0.1 and 14.1.2.4-14.1.3, cooperation between malicious HTTP client code and a malicious server may cause TMM to restart and generate a core file. Note: Software versions which have reached End of Software Development (EoSD) are not evaluated.

Which versions are affected by CVE-2021-22977?

It affects 14 products.

Products include F5 Big-Ip Access Policy Manager, F5 Big-Ip Advanced Firewall Manager, F5 Big-Ip Advanced Web Application Firewall, F5 Big-Ip Analytics, F5 Big-Ip Application Acceleration Manager, F5 Big-Ip Application Security Manager and 8 more.

How do I fix CVE-2021-22977?

No fix has been published for CVE-2021-22977 yet. Limit exposure of the affected software until one is available.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2021-22977 being exploited?

There is no known exploitation of CVE-2021-22977 in the wild and no public exploit code.

Other vulnerabilities in F5 Big-Ip Access Policy Manager

• CVE-2023-46747 F5 BIG-IP Configuration Utility Authentication Bypass Exploited Critical 9.8
• CVE-2022-1388 F5 BIG-IP Missing Authentication Exploited Critical 9.8
• CVE-2021-22986 F5 BIG-IP and BIG-IQ Centralized Management iControl REST Remote Code Execution Exploited Critical 9.8
• CVE-2021-22991 F5 BIG-IP Traffic Management Microkernel Buffer Overflow Exploited Critical 9.8
• CVE-2020-5902 F5 BIG-IP Traffic Management User Interface (TMUI) Remote Code Execution Exploited Critical 9.8

All F5 Big-Ip Access Policy Manager vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-ch8w-w4pc-hwjx.