How severe is CVE-2018-5542?

CVE-2018-5542 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-2018-5542 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-5542?

CVE-2018-5542 primarily affects F5 Big-ip Local Traffic Manager. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-5542?

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-2018-5542 published?

CVE-2018-5542 was published on 2018-07-25 and last updated on 2026-06-17.

CVE-2018-5542

CVE-2018-5542 is a high-severity vulnerability in F5 Big-ip Local Traffic 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-20.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 6.8
EPSS exploit prediction: 1% (65th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: F5 Big-ip Local Traffic Manager
Published: 2018-07-25
Last modified: 2026-06-17

Description

F5 BIG-IP 13.0.0-13.0.1, 12.1.0-12.1.3.6, or 11.2.1-11.6.3.2 HTTPS health monitors do not validate the identity of the monitored server.

Frequently asked questions

What is CVE-2018-5542?: F5 BIG-IP 13.0.0-13.0.1, 12.1.0-12.1.3.6, or 11.2.1-11.6.3.2 HTTPS health monitors do not validate the identity of the monitored server.
How severe is CVE-2018-5542?: CVE-2018-5542 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-2018-5542 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-5542?: CVE-2018-5542 primarily affects F5 Big-ip Local Traffic Manager. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-5542?: 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-2018-5542 published?: CVE-2018-5542 was published on 2018-07-25 and last updated on 2026-06-17.

References

https://support.f5.com/csp/article/K05112543

Affected products (13)

cpe:2.3:a:f5:big-ip_local_traffic_manager:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_application_acceleration_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_access_policy_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_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_policy_enforcement_manager:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_webaccelerator:*:*:*:*:*:*:*:*

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