Critical F5 BIG-IP Vulnerability 

THE THREAT

eSentire is aware of reports of Proof-of-Concept (PoC) exploit code and attacks in the wild exploiting the F5 BIG-IP vulnerability CVE-2022-1388 (CVSS: 9.8). The vulnerability was initially disclosed on May 4th and is tracked as an authentication bypass vulnerability. Exploitation could allow a threat actor to gain initial access to victim organizations and spread laterally within the network.

The public release of PoC exploit code is expected to result in an increase of attacks in the immediate future. All organizations making use of BIG-IP are strongly recommended to apply the relevant security patches immediately in order to reduce the likelihood of exploitation.

What we’re doing about it

• eSentire Managed Vulnerability Service has plugins in place to detect CVE-2022-1388
• eSentire MDR for Endpoint detects standard post-compromise activity
• IP addresses associated with real-world exploitation are blocked via eSentire’s Global Block List
• eSentire’s Threat Response Unit (TRU) has swept for clients with impacted products
  • Impacted organizations have been notified through the Security Operations Center (SOC)
• Security teams from eSentire are reviewing the publicly available PoC exploit code for additional detection opportunities

What you should do about it

• After performing a business impact review, apply the relevant security patches released by F5
  • If patching is not immediately possible, F5 has provided alternative mitigations that may be applied until security patches are deployed

Additional information

CVE-2022-1388 affects the BIG-IP iControl REST authentication component of BIG-IP networking devices. The vulnerability may be exploited by an unauthenticated threat actor with network access. According to public reporting, exploit attempts observed to date are focused on the deployment of webshells. The first reports of attacks in the wild appeared on May 7th and functional public PoC exploit code was confirmed on May 9th. The eSentire Threat Response Unit (TRU) assesses with high confidence that widespread exploitation leading to the deployment of varied payloads will occur in the near future.

Impacted BIG-IP Versions:

• 16.1.0 - 16.1.2
• 15.1.0 - 15.1.5
• 14.1.0 - 14.1.4
• 13.1.0 - 13.1.4
• 12.1.0 - 12.1.6
• 11.6.1 - 11.6.5

It should be noted that versions 12.1.0 - 12.1.6 and 11.6.1 - 11.6.5 are End of Life (EOL) and will not receive any updates or security patches. Organizations employing these versions are urged to apply the temporary mitigations and upgrade to a maintained version of the BIG-IP product.

References:

[1] https://support.f5.com/csp/article/K23605346