How severe is CVE-2026-42920?

CVE-2026-42920 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-2026-42920 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-42920?

CVE-2026-42920 primarily affects F5 Big-ip Access Policy Manager. In total, 42 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-42920?

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.

Does CVE-2026-42920 have an EU (EUVD) identifier?

Yes. CVE-2026-42920 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-30004.

When was CVE-2026-42920 published?

CVE-2026-42920 was published on 2026-05-13 and last updated on 2026-06-18.

CVE-2026-42920

CVE-2026-42920 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. The underlying weakness is classified as CWE-835.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v4: 8.7
EPSS exploit prediction: 0% (18th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-30004
Weakness: CWE-835
Affected product: F5 Big-ip Access Policy Manager
Published: 2026-05-13
Last modified: 2026-06-18

Description

When a Client SSL profile is configured with Allow Dynamic Record Sizing on a UDP virtual server, undisclosed traffic can cause the Traffic Management Microkernel (TMM) to terminate. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Frequently asked questions

What is CVE-2026-42920?: When a Client SSL profile is configured with Allow Dynamic Record Sizing on a UDP virtual server, undisclosed traffic can cause the Traffic Management Microkernel (TMM) to terminate. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
How severe is CVE-2026-42920?: CVE-2026-42920 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-2026-42920 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-42920?: CVE-2026-42920 primarily affects F5 Big-ip Access Policy Manager. In total, 42 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-42920?: 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.
Does CVE-2026-42920 have an EU (EUVD) identifier?: Yes. CVE-2026-42920 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-30004.
When was CVE-2026-42920 published?: CVE-2026-42920 was published on 2026-05-13 and last updated on 2026-06-18.

References

https://my.f5.com/manage/s/article/K000160901

Affected products (42)

cpe:2.3:a:f5:big-ip_access_policy_manager:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_advanced_firewall_manager:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_advanced_web_application_firewall:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_analytics:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_application_acceleration_manager:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_application_security_manager:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_application_visibility_and_reporting:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_automation_toolchain:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_carrier-grade_nat:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_container_ingress_services:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_ddos_hybrid_defender:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_domain_name_system:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_edge_gateway:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_fraud_protection_service:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_global_traffic_manager:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_link_controller:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_local_traffic_manager:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_policy_enforcement_manager:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_ssl_orchestrator:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_webaccelerator:21.0.0:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_websafe:21.0.0:*:*:*:*:*:*:*
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_advanced_web_application_firewall:*:*:*:*:*:*:*:*
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_application_visibility_and_reporting:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_automation_toolchain:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_carrier-grade_nat:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_container_ingress_services:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_ddos_hybrid_defender:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_domain_name_system:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_edge_gateway:*:*:*:*:*:*:*:*
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:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_ssl_orchestrator:*:*:*:*:*:*:*:*

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