F5 BIG-IP up to Certificate Authentication certificate validation

CVSS Meta Temp Score
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CTI Interest Score
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A vulnerability was found in F5 BIG-IP up to (Firewall Software). It has been classified as problematic. Affected is some unknown processing of the component Certificate Authentication. The manipulation with an unknown input leads to a certificate validation vulnerability. CWE is classifying the issue as CWE-295. The product does not validate, or incorrectly validates, a certificate. This is going to have an impact on availability. CVE summarizes:

On F5 BIG-IP versions 13.0.0 -, attackers may be able to disrupt services on the BIG-IP system with maliciously crafted client certificate. This vulnerability affects virtual servers associated with Client SSL profile which enables the use of client certificate authentication. Client certificate authentication is not enabled by default in Client SSL profile. There is no control plane exposure.

The bug was discovered 03/22/2018. The weakness was presented 03/22/2018 (Website). The advisory is available at support.f5.com. This vulnerability is traded as CVE-2018-5502 since 01/12/2018. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1587.003 by the MITRE ATT&CK project.

The vulnerability scanner Nessus provides a plugin with the ID 118660 (F5 Networks BIG-IP : BIG-IP Client SSL vulnerability (K43121447)), 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 370841 (F5 BIG-IP ASM TMM DNS Requests and Client SSL Denial of Service Vulnerability (K23520761,K43121447)).

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 (118660).







CPE 2.3info

CPE 2.2info


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

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
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NVD Base Score: 7.5
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Class: Certificate validation
CWE: CWE-295 / CWE-287

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

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Nessus ID: 118660
Nessus Name: F5 Networks BIG-IP : BIG-IP Client SSL vulnerability (K43121447)
Nessus File: 🔍
Nessus Risk: 🔍
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Threat Intelligenceinfo

Interest: 🔍
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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 🔍
03/23/2018 +1 days 🔍
11/02/2018 +224 days 🔍
02/22/2023 +1573 days 🔍


Vendor: f5.com

Advisory: K43121447
Status: Not defined
Confirmation: 🔍

CVE: CVE-2018-5502 (🔍)
SecurityTracker: 1040561


Created: 03/23/2018 10:04 AM
Updated: 02/22/2023 04:00 PM
Changes: 03/23/2018 10:04 AM (62), 01/15/2020 09:21 PM (8), 02/05/2021 06:27 PM (3), 02/22/2023 04:00 PM (3)
Complete: 🔍
Cache ID: 34:F5D:40


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