F5 BIG-IP up to TMM input validation

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.

A vulnerability classified as problematic was found in F5 BIG-IP up to (Firewall Software). This vulnerability affects an unknown part of the component TMM. The manipulation with an unknown input leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect availability. CVE summarizes:

On F5 BIG-IP versions 13.0.0 or 12.1.0 -, 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.

The bug was discovered 03/22/2018. The weakness was disclosed 03/22/2018 (Website). The advisory is available at support.f5.com. This vulnerability was named CVE-2018-5509 since 01/12/2018. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. The technical details are unknown and an exploit is not available.

The vulnerability scanner Nessus provides a plugin with the ID 118671 (F5 Networks BIG-IP : TMOS vulnerability (K49440608)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family F5 Networks Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 370840 (F5 BIG-IP ASM TMOS Denial of Service Vulnerability (K49440608)).

Upgrading eliminates this vulnerability. A possible mitigation has been published before and not just after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (118671).







CPE 2.3info

CPE 2.2info


VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍


VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.5
NVD Vector: 🔍



VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍


Class: Input validation

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍


Nessus ID: 118671
Nessus Name: F5 Networks BIG-IP : TMOS vulnerability (K49440608)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍


Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍


01/12/2018 🔍
03/21/2018 +68 days 🔍
03/22/2018 +1 days 🔍
03/22/2018 +0 days 🔍
03/22/2018 +0 days 🔍
03/22/2018 +0 days 🔍
03/23/2018 +1 days 🔍
11/02/2018 +224 days 🔍
02/22/2023 +1573 days 🔍


Vendor: f5.com

Advisory: K49440608
Status: Not defined
Confirmation: 🔍

CVE: CVE-2018-5509 (🔍)
SecurityTracker: 1040562
SecurityFocus: 103504 - Multiple F5 BIG-IP Products CVE-2018-5509 Remote Denial of Service Vulnerability


Created: 03/23/2018 10:05 AM
Updated: 02/22/2023 04:30 PM
Changes: 03/23/2018 10:05 AM (64), 01/16/2020 07:00 AM (10), 02/06/2021 06:14 AM (3), 02/22/2023 04:30 PM (3)
Complete: 🔍
Cache ID: 44:C34:40


No comments yet. Languages: en.

Please log in to comment.

Do you know our Splunk app?

Download it now for free!