CVE-2021-23047 Denial of service in BIG-IP APM

What is CVE-2021-23047?

CVE-2021-23047 is a medium-severity denial of service vulnerability in F5 Big-Ip Access Policy Manager, published on 14 Sep 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

On version 16.x before 16.1.0, 15.1.x before 15.1.3.1, 14.1.x before 14.1.4.3, and all versions of 13.1.x, 12.1.x and 11.6.x, when BIG-IP APM performs Online Certificate Status Protocol (OCSP) verification of a certificate that contains Authority Information Access (AIA), undisclosed requests may cause an increase in memory use. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Weakness: CWE-400

Which versions are affected by CVE-2021-23047?

It affects 1 product.

Products include F5 Big-Ip Access Policy Manager.

How do I fix CVE-2021-23047?

No fix has been published for CVE-2021-23047 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-2021-23047 being exploited?

There is no known exploitation of CVE-2021-23047 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-5cjp-4h3f-m7r2.