CVE-2022-1388: Authentication Bypass in F5 BIG-IP
F5 patched an authentication bypass in its BIG-IP product family that could lead to arbitrary command execution. This vulnerability is actively being exploited.
Update May 10: The Identifying Affected Systems section now reflects the availability of a remote check. The Background section has also been updated based on active exploitation.
As part of its Quarterly Security Notification for May 2022, F5 patched CVE-2022-1388, a critical authentication bypass vulnerability in BIG-IP, a family of hardware and software solutions used for application delivery and centralized device management.
Attackers have capitalized on previously disclosed flaws in BIG-IP: CVE-2021-22986, a flaw in the iControl REST component of BIG-IP and CVE-2020-5902, a flaw in the BIG-IP traffic management user interface, have both been exploited in the wild. The Security Response Team included CVE-2020-5902 among its top 5 vulnerabilities in the 2020 Threat Landscape Retrospective due to the scope of exploitation. On May 9, shortly after the first proofs-of-concept were published, exploitation attempts were detected in the wild.
CVE-2022-1388 is an authentication bypass vulnerability in the REST component of BIG-IP’s iControl API that was assigned a CVSSv3 score of 9.8. The iControl REST API is used for the management and configuration of BIG-IP devices. CVE-2022-1388 could be exploited by an unauthenticated attacker with network access to the management port or self IP addresses of devices that use BIG-IP. Exploitation would allow the attacker to execute arbitrary system commands, create and delete files and disable services.
Proof of concept
On May 6, the Horizon3 Attack Team posted on Twitter that one of their researchers, James Horseman, had developed a proof-of-concept (PoC) for CVE-2022-1388. They held off publishing this PoC until May 9. Also on May 9, Ja502n published another PoC on Twitter.
While patching is the recommended course of action, F5 has provided some mitigation guidance if it is not immediately possible. To reduce the attack service, organizations can restrict access to the vulnerable iControl REST API to trusted networks and devices. It is advisable to disallow access to device management interfaces from untrusted networks.
The following table lists the branches of BIG-IP, affected versions and fixed versions:
|Branch||Affected Versions||Fixed Version|
|16.x||16.1.0 - 16.1.2||188.8.131.52|
|15.x||15.1.0 - 15.1.5||184.108.40.206|
|14.x||14.1.0 - 14.1.4||220.127.116.11|
|13.x||13.1.0 - 13.1.4||13.1.5|
|12.x||12.1.0 - 12.1.6||Will not fix|
|11.x||11.6.1 - 11.6.5||Will not fix|
Identifying affected systems
A list of Tenable plugins to identify this vulnerability can be found here. A compliance audit file is available here to check for the httpd mitigation. We have also released a remote check plugin to determine if you F5 BIG-IP deployments are vulnerable to exploit with CVE-2022-1388.
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Update May 9: The Proof-of-Concept section now provides links to two proofs-of-concept published after initial publication.
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