CVE-2020-5921
CVE-2020-5921 is a high-severity vulnerability in F5 Big-ip Access Policy Manager with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 1% (60th percentile)
- Actively exploited: Not listed in CISA KEV
- Affected product: F5 Big-ip Access Policy Manager
- Published:
- Last modified:
Description
in BIG-IP versions 15.1.0-15.1.0.4, 15.0.0-15.0.1.3, 14.1.0-14.1.2.6, 13.1.0-13.1.3.4, 12.1.0-12.1.5.1, and 11.6.1-11.6.5.2, Syn flood causes large number of MCPD context messages destined to secondary blades consuming memory leading to MCPD failure. This issue affects only VIPRION hosts with two or more blades installed. Single-blade VIPRION hosts are not affected.
Frequently asked questions
- What is CVE-2020-5921?
- in BIG-IP versions 15.1.0-15.1.0.4, 15.0.0-15.0.1.3, 14.1.0-14.1.2.6, 13.1.0-13.1.3.4, 12.1.0-12.1.5.1, and 11.6.1-11.6.5.2, Syn flood causes large number of MCPD context messages destined to secondary blades consuming memory leading to MCPD failure. This issue affects only VIPRION hosts with two or more blades installed. Single-blade VIPRION hosts are not affected.
- How severe is CVE-2020-5921?
- CVE-2020-5921 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2020-5921 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-5921?
- CVE-2020-5921 primarily affects F5 Big-ip Access Policy Manager. In total, 11 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2020-5921?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2020-5921 published?
- CVE-2020-5921 was published on 2020-08-26 and last updated on 2026-06-17.
References
Affected products (11)
- cpe:2.3:a:f5:big-ip_access_policy_manager:*:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_advanced_firewall_manager:*:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_analytics:*:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_application_acceleration_manager:*:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_application_security_manager:*:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_domain_name_system:*:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_fraud_protection_service:*:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_global_traffic_manager:*:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_link_controller:*:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_local_traffic_manager:*:*:*:*:*:*:*:*
- cpe:2.3:a:f5:big-ip_policy_enforcement_manager:*:*:*:*:*:*:*:*
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