CVE intelligence and bounded remediation

CVE-2021-23053 — F5 Big-Ip Advanced Web Application Firewall security vulnerability

Medium CVSS 5.3

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.

Severity
Medium
CVSS
5.3 (3.1)
Published
2021-09-14
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-400, CWE-770

Affected products

  • f5 / big-ip_advanced_web_application_firewall
  • f5 / big-ip_application_security_manager

Showing 2 representative product identities from 6 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

Resource exhaustion and denial of service

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify attacker-influenced work factors including input size, nesting, compression, fan-out, regex cost, allocation, recursion, retries, and connection lifetime.
  • Map per-request and shared CPU, memory, disk, descriptor, thread, queue, and downstream-service limits.
  • Determine whether authentication, tenancy, quotas, and rate controls apply before expensive processing begins.

Remediate safely

  • Bound input size, nesting, expansion, work, concurrency, queue depth, retries, and execution time before resource-intensive processing.
  • Release resources on every success, error, cancellation, and timeout path and use backpressure instead of unbounded buffering.
  • Update affected components and add small deterministic tests that assert resource ceilings rather than exhausting a host.

Authoritative sources

Complete CVE record and remediation plan

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