QID 375956

Date Published: 2021-10-13

QID 375956: F5 BIG-IP Application Security Manager (ASM), Local Traffic Manager (LTM), Access Policy Manager (APM) Open Secure Sockets Layer (OpenSSL) Vulnerability (K19559038)

F5 BIG-IP ASM (Application Security Manager) is a flexible web application firewall that secures web applications in traditional, virtual, and private cloud environments.
F5 BIG-IP (LTM) Local Traffic Manager is the most popular module offered on F5 Networks BIG-IP platform. The real power of the LTM is it is a Full Proxy, allowing you to augment client and server side connections. All while making informed load balancing decisions on availability, performance, and persistence.
F5 BIG-IP Access Policy Manager (APM) is a secure, flexible, high-performance solution that provides unified global access to your network, cloud, and applications.

If a malicious actor can cause an application to directly construct an ASN1_STRING and then process it through one of the affected OpenSSL functions then this issue could be hit. This might result in a crash (causing a Denial of Service attack). It could also result in the disclosure of private memory contents (such as private keys, or sensitive plaintext). Fixed in OpenSSL 1.1.1l (Affected 1.1.1-1.1.1k). Fixed in OpenSSL 1.0.2za (Affected 1.0.2-1.0.2y). (CVE-2021-3712) (CVE-2020-27618)

Vulnerable Component: BIG-IP ASM, APM, LTM

Affected Versions:
16.0.0 - 16.1.0
15.1.0 - 15.1.3
14.1.0 - 14.1.4
13.1.0 - 13.1.4
12.1.0 - 12.1.6
11.6.1 - 11.6.5

QID Detection Logic(Authenticated):
This QID checks for the vulnerable versions of F5 BIG-IP devices using the tmsh command.

A remote attacker can exploit the vulnerability by triggering an application to create an ASN1_STRING and process it with an affected OpenSSL function to access restricted information or cause a denial-of-service (DoS).

  • CVSS V3 rated as High - 7.4 severity.
  • CVSS V2 rated as Medium - 5.8 severity.
  • Solution
    The vendor has released patch, for more information please visit: K19559038
    Vendor References

    CVEs related to QID 375956

    Software Advisories
    Advisory ID Software Component Link
    K19559038 URL Logo support.f5.com/csp/article/K19559038
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