How severe is CVE-2020-5876?

CVE-2020-5876 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-5876 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-5876?

CVE-2020-5876 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-2020-5876?

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-2020-5876 published?

CVE-2020-5876 was published on 2020-04-30 and last updated on 2026-06-17.

CVE-2020-5876

CVE-2020-5876 is a high-severity vulnerability in F5 Big-ip Access Policy Manager with a CVSS 3.x base score of 8.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-319.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 6.8
EPSS exploit prediction: 1% (43rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-319
Affected product: F5 Big-ip Access Policy Manager
Published: 2020-04-30
Last modified: 2026-06-17

Description

On BIG-IP 15.0.0-15.0.1.3, 14.1.0-14.1.2.3, 13.1.0-13.1.3.3, 12.1.0-12.1.5.1, and 11.6.1-11.6.5.1, a race condition exists where mcpd and other processes may make unencrypted connection attempts to a new configuration sync peer. The race condition can occur when changing the ConfigSync IP address of a peer, adding a new peer, or when the Traffic Management Microkernel (TMM) first starts up.

Frequently asked questions

What is CVE-2020-5876?: On BIG-IP 15.0.0-15.0.1.3, 14.1.0-14.1.2.3, 13.1.0-13.1.3.3, 12.1.0-12.1.5.1, and 11.6.1-11.6.5.1, a race condition exists where mcpd and other processes may make unencrypted connection attempts to a new configuration sync peer. The race condition can occur when changing the ConfigSync IP address of a peer, adding a new peer, or when the Traffic Management Microkernel (TMM) first starts up.
How severe is CVE-2020-5876?: CVE-2020-5876 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-5876 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-5876?: CVE-2020-5876 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-2020-5876?: 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-2020-5876 published?: CVE-2020-5876 was published on 2020-04-30 and last updated on 2026-06-17.

References

https://support.f5.com/csp/article/K32121038

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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