Vulnerability Monitor

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CVE-2021-23000


On BIG-IP versions 13.1.3.4-13.1.3.6 and 12.1.5.2, if the tmm.http.rfc.enforcement BigDB key is enabled in a BIG-IP system, or the Bad host header value is checked in the AFM HTTP security profile associated with a virtual server, in rare instances, a specific sequence of malicious requests may cause TMM to restart. Note: Software versions which have reached End of Software Development (EoSD) are not evaluated.


Security Impact Summary

This vulnerability carries a HIGH severity rating with a CVSS v3.1 score of 7.5, indicating it can be exploited remotely over the network with relatively low complexity without requiring user interaction and does not require pre-existing privileges . The vulnerability impacts and availability (service disruption) for affected systems. Impacting 14 products from f5, from f5, from f5 and 11 others, organizations running these solutions should prioritize assessment and patching.

Historical Context

Reported in 2021, this vulnerability emerged during an era marked by increased sophistication in supply chain attacks, cloud infrastructure vulnerabilities, and software-as-a-service (SaaS) security challenges. Security practices during this period emphasized zero-trust architectures, container security, and API protection.


Published

2021-03-31T18:15:15.223

Last Modified

2024-11-21T05:51:07.640

Status

Modified

Source

[email protected]

Severity

CVSSv3.1: 7.5 (HIGH)

CVSSv2 Vector

AV:N/AC:M/Au:N/C:N/I:N/A:P

  • Access Vector: NETWORK
  • Access Complexity: MEDIUM
  • Authentication: NONE
  • Confidentiality Impact: NONE
  • Integrity Impact: NONE
  • Availability Impact: PARTIAL
Exploitability Score

8.6

Impact Score

2.9

Weaknesses
  • Type: Primary
    NVD-CWE-noinfo

Affected Vendors & Products
Type Vendor Product Version/Range Vulnerable?
Application f5 big-ip_access_policy_manager < 13.1.3.6 Yes
Application f5 big-ip_access_policy_manager 12.1.5.2 Yes
Application f5 big-ip_advanced_firewall_manager < 13.1.3.6 Yes
Application f5 big-ip_advanced_firewall_manager 12.1.5.2 Yes
Application f5 big-ip_advanced_web_application_firewall < 13.1.3.6 Yes
Application f5 big-ip_advanced_web_application_firewall 12.1.5.2 Yes
Application f5 big-ip_analytics < 13.1.3.6 Yes
Application f5 big-ip_analytics 12.1.5.2 Yes
Application f5 big-ip_application_acceleration_manager < 13.1.3.6 Yes
Application f5 big-ip_application_acceleration_manager 12.1.5.2 Yes
Application f5 big-ip_application_security_manager < 13.1.3.6 Yes
Application f5 big-ip_application_security_manager 12.1.5.2 Yes
Application f5 big-ip_ddos_hybrid_defender < 13.1.3.6 Yes
Application f5 big-ip_ddos_hybrid_defender 12.1.5.2 Yes
Application f5 big-ip_domain_name_system < 13.1.3.6 Yes
Application f5 big-ip_domain_name_system 12.1.5.2 Yes
Application f5 big-ip_fraud_protection_service < 13.1.3.6 Yes
Application f5 big-ip_fraud_protection_service 12.1.5.2 Yes
Application f5 big-ip_global_traffic_manager < 13.1.3.6 Yes
Application f5 big-ip_global_traffic_manager 12.1.5.2 Yes
Application f5 big-ip_link_controller < 13.1.3.6 Yes
Application f5 big-ip_link_controller 12.1.5.2 Yes
Application f5 big-ip_local_traffic_manager < 13.1.3.6 Yes
Application f5 big-ip_local_traffic_manager 12.1.5.2 Yes
Application f5 big-ip_policy_enforcement_manager < 13.1.3.6 Yes
Application f5 big-ip_policy_enforcement_manager 12.1.5.2 Yes
Application f5 ssl_orchestrator < 13.1.3.6 Yes
Application f5 ssl_orchestrator 12.1.5.2 Yes

References

How SecUtils Interprets This CVE

SecUtils normalizes and enriches National Vulnerability Database (NVD) records by standardizing vendor and product identifiers, aggregating vulnerability metadata from both NVD and MITRE sources, and providing structured context for security teams. For f5's affected products, we extract Common Platform Enumeration (CPE) data, Common Weakness Enumeration (CWE) classifications, CVSS severity metrics, and reference data to enable rapid vulnerability prioritization and asset correlation. This record contains no exploit code, proof-of-concept instructions, or attack methodologies—only defensive intelligence necessary for patch management, risk assessment, and security operations.