CVE-2018-5509

Severity: high (CVSS 7.5 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2018-03-22 · updated 2026-06-17
Weakness: CWE-20

Description

On F5 BIG-IP versions 13.0.0 or 12.1.0 - 12.1.3.1, when a specifically configured virtual server receives traffic of an undisclosed nature, TMM will crash and take the configured failover action, potentially causing a denial of service. The configuration which exposes this issue is not common and in general does not work when enabled in previous versions of BIG-IP. Starting in 12.1.0, BIG-IP will crash if the configuration which exposes this issue is enabled and the virtual server receives non TCP traffic. With the fix of this issue, additional configuration validation logic has been added to prevent this configuration from being applied to a virtual server. There is only data plane exposure to this issue with a non-standard configuration. There is no control plane exposure.

Affected products

F5 BIG-IP APM: from 12.1.0 before 12.1.3.2; from 13.0.0 before 13.1.0.4 — fixed in 12.1.3.2, 13.1.0.4
BIG-IP: from 12.1.0 before 12.1.3.2; from 13.0.0 before 13.1.0.4 — fixed in 12.1.3.2, 13.1.0.4
F5 Networks, Inc. BIG-IP (AAM): from 12.1.0 before 12.1.3.2; from 13.0.0 before 13.1.0.4 — fixed in 12.1.3.2, 13.1.0.4
BIG-IP ASM: from 12.1.0 before 12.3.1.2; from 13.0.0 before 13.1.0.4 — fixed in 12.3.1.2, 13.1.0.4
F5 Big-Ip Link Controller: from 12.1.0 before 12.1.3.2; from 13.0.0 before 13.1.0.4 — fixed in 12.1.3.2, 13.1.0.4
F5 BIG-IP (LTM): from 12.1.0 before 12.1.3.2; from 13.0.0 before 13.1.0.4 — fixed in 12.1.3.2, 13.1.0.4
F5 Networks, Inc. BIG-IP (PEM): from 12.1.0 before 12.1.3.2; from 13.0.0 before 13.1.0.4 — fixed in 12.1.3.2, 13.1.0.4
F5 Big-Ip Websafe: 1.0.0

How to fix

Upgrade to a fixed version: F5 BIG-IP APM 12.1.3.2, 13.1.0.4; BIG-IP 12.1.3.2, 13.1.0.4; F5 Networks, Inc. BIG-IP (AAM) 12.1.3.2, 13.1.0.4; BIG-IP ASM 12.3.1.2, 13.1.0.4; F5 Big-Ip Link Controller 12.1.3.2, 13.1.0.4; F5 BIG-IP (LTM) 12.1.3.2, 13.1.0.4; F5 Networks, Inc. BIG-IP (PEM) 12.1.3.2, 13.1.0.4. Check the vendor advisory for mitigations.

References

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