CVE-2018-5501

In some circumstances, on F5 BIG-IP systems running 13.0.0, 12.1.0 - 12.1.3.1, any 11.6.x or 11.5.x release, or 11.2.1, TCP DNS profile allows excessive buffering due to lack of flow control.

Published: 2018-03-01 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2018-5501 is rated Moderate Risk (48.3/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.41%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2018-5501

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.89% 1.41% +0.52%
2 2025-11-21 0.68% 0.89% +0.22%
3 2025-11-18 0.68%

Full EPSS history (9 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2018-5501

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.9 3.0 MEDIUM
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.2 3.6 [email protected]
4.3 2.0 MEDIUM
AV:N/AC:M/Au:N/C:N/I:N/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
8.6 2.9 [email protected]

Weakness enumeration for CVE-2018-5501

Affected software / configurations for CVE-2018-5501

Vendor Product Version Raw CPE
f5 big-ip_local_traffic_manager >= 11.5.1, <= 11.5.4 cpe:2.3:a:f5:big-ip_local_traffic_manager:*:*:*:*:*:*:*:*
f5 big-ip_local_traffic_manager >= 11.6.1, <= 11.6.2 cpe:2.3:a:f5:big-ip_local_traffic_manager:*:*:*:*:*:*:*:*
f5 big-ip_local_traffic_manager >= 12.1.0, <= 12.1.3 cpe:2.3:a:f5:big-ip_local_traffic_manager:*:*:*:*:*:*:*:*
f5 big-ip_local_traffic_manager 11.2.1 cpe:2.3:a:f5:big-ip_local_traffic_manager:11.2.1:*:*:*:*:*:*:*
f5 big-ip_local_traffic_manager 13.0.0 cpe:2.3:a:f5:big-ip_local_traffic_manager:13.0.0:*:*:*:*:*:*:*
f5 big-ip_application_acceleration_manager >= 11.5.1, <= 11.5.4 cpe:2.3:a:f5:big-ip_application_acceleration_manager:*:*:*:*:*:*:*:*
f5 big-ip_application_acceleration_manager >= 11.6.1, <= 11.6.2 cpe:2.3:a:f5:big-ip_application_acceleration_manager:*:*:*:*:*:*:*:*
f5 big-ip_application_acceleration_manager >= 12.1.0, <= 12.1.3 cpe:2.3:a:f5:big-ip_application_acceleration_manager:*:*:*:*:*:*:*:*
f5 big-ip_application_acceleration_manager 11.2.1 cpe:2.3:a:f5:big-ip_application_acceleration_manager:11.2.1:*:*:*:*:*:*:*
f5 big-ip_application_acceleration_manager 13.0.0 cpe:2.3:a:f5:big-ip_application_acceleration_manager:13.0.0:*:*:*:*:*:*:*
f5 big-ip_advanced_firewall_manager >= 11.5.1, <= 11.5.4 cpe:2.3:a:f5:big-ip_advanced_firewall_manager:*:*:*:*:*:*:*:*
f5 big-ip_advanced_firewall_manager >= 11.6.1, <= 11.6.2 cpe:2.3:a:f5:big-ip_advanced_firewall_manager:*:*:*:*:*:*:*:*
f5 big-ip_advanced_firewall_manager >= 12.1.0, <= 12.1.3 cpe:2.3:a:f5:big-ip_advanced_firewall_manager:*:*:*:*:*:*:*:*
f5 big-ip_advanced_firewall_manager 11.2.1 cpe:2.3:a:f5:big-ip_advanced_firewall_manager:11.2.1:*:*:*:*:*:*:*
f5 big-ip_advanced_firewall_manager 13.0.0 cpe:2.3:a:f5:big-ip_advanced_firewall_manager:13.0.0:*:*:*:*:*:*:*
f5 big-ip_analytics >= 11.5.1, <= 11.5.4 cpe:2.3:a:f5:big-ip_analytics:*:*:*:*:*:*:*:*
f5 big-ip_analytics >= 11.6.1, <= 11.6.2 cpe:2.3:a:f5:big-ip_analytics:*:*:*:*:*:*:*:*
f5 big-ip_analytics >= 12.1.0, <= 12.1.3 cpe:2.3:a:f5:big-ip_analytics:*:*:*:*:*:*:*:*
f5 big-ip_analytics 11.2.1 cpe:2.3:a:f5:big-ip_analytics:11.2.1:*:*:*:*:*:*:*
f5 big-ip_analytics 13.0.0 cpe:2.3:a:f5:big-ip_analytics:13.0.0:*:*:*:*:*:*:*
f5 big-ip_access_policy_manager >= 11.5.1, <= 11.5.4 cpe:2.3:a:f5:big-ip_access_policy_manager:*:*:*:*:*:*:*:*
f5 big-ip_access_policy_manager >= 11.6.1, <= 11.6.2 cpe:2.3:a:f5:big-ip_access_policy_manager:*:*:*:*:*:*:*:*
f5 big-ip_access_policy_manager >= 12.1.0, <= 12.1.3 cpe:2.3:a:f5:big-ip_access_policy_manager:*:*:*:*:*:*:*:*
f5 big-ip_access_policy_manager 11.2.1 cpe:2.3:a:f5:big-ip_access_policy_manager:11.2.1:*:*:*:*:*:*:*
f5 big-ip_access_policy_manager 13.0.0 cpe:2.3:a:f5:big-ip_access_policy_manager:13.0.0:*:*:*:*:*:*:*
f5 big-ip_application_security_manager >= 11.5.1, <= 11.5.4 cpe:2.3:a:f5:big-ip_application_security_manager:*:*:*:*:*:*:*:*
f5 big-ip_application_security_manager >= 11.6.1, <= 11.6.2 cpe:2.3:a:f5:big-ip_application_security_manager:*:*:*:*:*:*:*:*
f5 big-ip_application_security_manager >= 12.1.0, <= 12.1.3 cpe:2.3:a:f5:big-ip_application_security_manager:*:*:*:*:*:*:*:*
f5 big-ip_application_security_manager 11.2.1 cpe:2.3:a:f5:big-ip_application_security_manager:11.2.1:*:*:*:*:*:*:*
f5 big-ip_application_security_manager 13.0.0 cpe:2.3:a:f5:big-ip_application_security_manager:13.0.0:*:*:*:*:*:*:*
f5 big-ip_dns >= 11.5.1, <= 11.5.4 cpe:2.3:a:f5:big-ip_dns:*:*:*:*:*:*:*:*
f5 big-ip_dns >= 11.6.1, <= 11.6.2 cpe:2.3:a:f5:big-ip_dns:*:*:*:*:*:*:*:*
f5 big-ip_dns >= 12.1.0, <= 12.1.3 cpe:2.3:a:f5:big-ip_dns:*:*:*:*:*:*:*:*
f5 big-ip_dns 11.2.1 cpe:2.3:a:f5:big-ip_dns:11.2.1:*:*:*:*:*:*:*
f5 big-ip_dns 13.0.0 cpe:2.3:a:f5:big-ip_dns:13.0.0:*:*:*:*:*:*:*
f5 big-ip_link_controller >= 11.5.1, <= 11.5.4 cpe:2.3:a:f5:big-ip_link_controller:*:*:*:*:*:*:*:*
f5 big-ip_link_controller >= 11.6.1, <= 11.6.2 cpe:2.3:a:f5:big-ip_link_controller:*:*:*:*:*:*:*:*
f5 big-ip_link_controller >= 12.1.0, <= 12.1.3 cpe:2.3:a:f5:big-ip_link_controller:*:*:*:*:*:*:*:*
f5 big-ip_link_controller 11.2.1 cpe:2.3:a:f5:big-ip_link_controller:11.2.1:*:*:*:*:*:*:*
f5 big-ip_link_controller 13.0.0 cpe:2.3:a:f5:big-ip_link_controller:13.0.0:*:*:*:*:*:*:*
f5 big-ip_policy_enforcement_manager >= 11.5.1, <= 11.5.4 cpe:2.3:a:f5:big-ip_policy_enforcement_manager:*:*:*:*:*:*:*:*
f5 big-ip_policy_enforcement_manager >= 11.6.1, <= 11.6.2 cpe:2.3:a:f5:big-ip_policy_enforcement_manager:*:*:*:*:*:*:*:*
f5 big-ip_policy_enforcement_manager >= 12.1.0, <= 12.1.3 cpe:2.3:a:f5:big-ip_policy_enforcement_manager:*:*:*:*:*:*:*:*
f5 big-ip_policy_enforcement_manager 11.2.1 cpe:2.3:a:f5:big-ip_policy_enforcement_manager:11.2.1:*:*:*:*:*:*:*
f5 big-ip_policy_enforcement_manager 13.0.0 cpe:2.3:a:f5:big-ip_policy_enforcement_manager:13.0.0:*:*:*:*:*:*:*
f5 big-ip_websafe >= 11.5.1, <= 11.5.4 cpe:2.3:a:f5:big-ip_websafe:*:*:*:*:*:*:*:*
f5 big-ip_websafe >= 11.6.1, <= 11.6.2 cpe:2.3:a:f5:big-ip_websafe:*:*:*:*:*:*:*:*
f5 big-ip_websafe >= 12.1.0, <= 12.1.3 cpe:2.3:a:f5:big-ip_websafe:*:*:*:*:*:*:*:*
f5 big-ip_websafe 11.2.1 cpe:2.3:a:f5:big-ip_websafe:11.2.1:*:*:*:*:*:*:*
f5 big-ip_websafe 13.0.0 cpe:2.3:a:f5:big-ip_websafe:13.0.0:*:*:*:*:*:*:*
f5 big-ip_edge_gateway >= 11.5.1, <= 11.5.4 cpe:2.3:a:f5:big-ip_edge_gateway:*:*:*:*:*:*:*:*
f5 big-ip_edge_gateway >= 11.6.1, <= 11.6.2 cpe:2.3:a:f5:big-ip_edge_gateway:*:*:*:*:*:*:*:*
f5 big-ip_edge_gateway >= 12.1.0, <= 12.1.3 cpe:2.3:a:f5:big-ip_edge_gateway:*:*:*:*:*:*:*:*
f5 big-ip_edge_gateway 11.2.1 cpe:2.3:a:f5:big-ip_edge_gateway:11.2.1:*:*:*:*:*:*:*
f5 big-ip_edge_gateway 13.0.0 cpe:2.3:a:f5:big-ip_edge_gateway:13.0.0:*:*:*:*:*:*:*
f5 big-ip_global_traffic_manager >= 11.5.1, <= 11.5.4 cpe:2.3:a:f5:big-ip_global_traffic_manager:*:*:*:*:*:*:*:*
f5 big-ip_global_traffic_manager >= 11.6.1, <= 11.6.2 cpe:2.3:a:f5:big-ip_global_traffic_manager:*:*:*:*:*:*:*:*
f5 big-ip_global_traffic_manager >= 12.1.0, <= 12.1.3 cpe:2.3:a:f5:big-ip_global_traffic_manager:*:*:*:*:*:*:*:*
f5 big-ip_global_traffic_manager 11.2.1 cpe:2.3:a:f5:big-ip_global_traffic_manager:11.2.1:*:*:*:*:*:*:*
f5 big-ip_global_traffic_manager 13.0.0 cpe:2.3:a:f5:big-ip_global_traffic_manager:13.0.0:*:*:*:*:*:*:*
f5 big-ip_webaccelerator >= 11.5.1, <= 11.5.4 cpe:2.3:a:f5:big-ip_webaccelerator:*:*:*:*:*:*:*:*
f5 big-ip_webaccelerator >= 11.6.1, <= 11.6.2 cpe:2.3:a:f5:big-ip_webaccelerator:*:*:*:*:*:*:*:*
f5 big-ip_webaccelerator >= 12.1.0, <= 12.1.3 cpe:2.3:a:f5:big-ip_webaccelerator:*:*:*:*:*:*:*:*
f5 big-ip_webaccelerator 11.2.1 cpe:2.3:a:f5:big-ip_webaccelerator:11.2.1:*:*:*:*:*:*:*
f5 big-ip_webaccelerator 13.0.0 cpe:2.3:a:f5:big-ip_webaccelerator:13.0.0:*:*:*:*:*:*:*

References for CVE-2018-5501

URL Tags
http://www.securityfocus.com/bid/103211 Third Party Advisory VDB Entry
https://support.f5.com/csp/article/K44200194 Vendor Advisory
cvelogic Threat Intelligence