CVE-2021-23053

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-09-14 · updated 2026-06-17
Weakness: CWE-400

Description

On version 15.1.x before 15.1.3, 14.1.x before 14.1.3.1, and 13.1.x before 13.1.3.6, when the brute force protection feature of BIG-IP Advanced WAF or BIG-IP ASM is enabled on a virtual server and the virtual server is under brute force attack, the MySQL database may run out of disk space due to lack of row limit on undisclosed tables in the MYSQL database. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Affected products

F5 Big-Ip Advanced Web Application Firewall: from 13.1.0 before 13.1.3.6; from 14.1.0 before 14.1.3.1; from 15.1.0 before 15.1.3 — fixed in 13.1.3.6, 14.1.3.1, 15.1.3
BIG-IP ASM: from 13.1.0 before 13.1.3.6; from 14.1.0 before 14.1.3.1; from 15.1.0 before 15.1.3 — fixed in 13.1.3.6, 14.1.3.1, 15.1.3

How to fix

Upgrade to a fixed version: F5 Big-Ip Advanced Web Application Firewall 13.1.3.6, 14.1.3.1, 15.1.3; BIG-IP ASM 13.1.3.6, 14.1.3.1, 15.1.3. Check the vendor advisory for mitigations.

References

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