How severe is CVE-2018-5520?

CVE-2018-5520 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2018-5520 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-2018-5520?

CVE-2018-5520 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-2018-5520?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2018-5520 published?

CVE-2018-5520 was published on 2018-05-02 and last updated on 2026-06-17.

CVE-2018-5520

CVE-2018-5520 is a medium-severity vulnerability in F5 Big-ip Local Traffic Manager with a CVSS 3.x base score of 4.4. 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-863.

Key facts

Severity: Medium (CVSS 3.x base score 4.4)
CVSS v2: 3.5
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-863
Affected product: F5 Big-ip Local Traffic Manager
Published: 2018-05-02
Last modified: 2026-06-17

Description

On an F5 BIG-IP 13.0.0-13.1.0.5, 12.1.0-12.1.3.1, or 11.2.1-11.6.3.1 system configured in Appliance mode, the TMOS Shell (tmsh) may allow an administrative user to use the dig utility to gain unauthorized access to file system resources.

Frequently asked questions

What is CVE-2018-5520?: On an F5 BIG-IP 13.0.0-13.1.0.5, 12.1.0-12.1.3.1, or 11.2.1-11.6.3.1 system configured in Appliance mode, the TMOS Shell (tmsh) may allow an administrative user to use the dig utility to gain unauthorized access to file system resources.
How severe is CVE-2018-5520?: CVE-2018-5520 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2018-5520 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-2018-5520?: CVE-2018-5520 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-2018-5520?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-5520 published?: CVE-2018-5520 was published on 2018-05-02 and last updated on 2026-06-17.

References

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_edge_gateway:*:*:*:*:*:*:*:*
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:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_websafe:*:*:*:*:*:*:*:*
cpe:2.3:a:f5:big-ip_domain_name_system:*:*:*:*:*:*:*:*

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