The U.S. Cybersecurity and Infrastructure Security Agency (CISA) issued an alert on Friday to warn organizations about the risk posed by a recently patched vulnerability affecting F5 Networks’ BIG-IP application delivery controller (ADC).
The critical security hole, identified as CVE-2020-5902, allows an attacker with access to the product’s Traffic Management User Interface (TMUI) configuration utility to obtain credentials and other sensitive data, intercept traffic, and execute arbitrary code or commands, resulting in the system getting completely compromised.
The issue was disclosed on July 1. At the time of disclosure, Positive Technologies, whose employees have been credited for reporting the vulnerability to F5, estimated that there had been thousands of vulnerable devices exposed to the internet, including many in the United States.
A proof-of-concept (PoC) exploit was released a few days later and the first exploitation attempts were spotted on July 5. F5, which released a patch before disclosure, tells customers to assume that their systems have been compromised if they’ve failed to install the patch for CVE-2020-5902.
CISA says government departments and agencies have been seeing scanning and reconnaissance activity associated with this flaw since July 6. The agency has been investigating several potential breaches resulting from the exploitation of this vulnerability, including against U.S. government and commercial organizations, and it has so far confirmed two instances where systems have been compromised.
CISA has advised organizations to immediately update their BIG-IP products and if they find evidence of attacks they should swiftly take action.
The agency’s recommendations in case of a breach include reimaging compromised hosts, resetting account passwords, limiting access to the vulnerable management interface, and implementing network segmentation to prevent the attacker from moving laterally within the network.