Researchers at Positive Technologies have published a proof-of-concept exploit for CVE-2020-3580. There are reports of researchers pursuing bug bounties using this exploit. Update June 28: The Background section has been updated to correct the initial publication date of Cisco's advisory. The Vendor Response section has also been updated.

CVE-2020-3580: Proof of Concept Published for Cisco ASA Flaw Patched in October

Multiple vulnerabilities in the web services interface of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to conduct cross-site scripting (XSS) attacks against a user of the web services interface of an affected device. The vulnerabilities are due to insufficient validation of user-supplied input by the web services interface of an affected device. An attacker could exploit these vulnerabilities by persuading a user of the interface to click a crafted link. A successful exploit could allow the attacker to execute arbitrary script code in the context of the interface or allow the attacker to access sensitive, browser-based information. Note: These vulnerabilities affect only specific AnyConnect and WebVPN configurations. For more information, see the Vulnerable Products section.

The version of Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software running on the remote web server is affected by a cross-site scripting vulnerability. An unauthenticated, remote attacker can exploit this, by convincing a user to click a specially crafted URL, to execute arbitrary script code in a user's browser session.
Please see the included Cisco BID and Cisco Security Advisory for more information.

According to its self-reported version, Cisco Firepower Threat Defense Software is affected by multiple vulnerabilities.
Please see the included Cisco BIDs and Cisco Security Advisory for more information.

According to its self-reported version, Cisco ASA Software is affected by multiple vulnerabilities.
Please see the included Cisco BIDs and Cisco Security Advisory for more information.

ID	Name	Product	Family	Severity
151442	Cisco ASA Software and FTD Software Web Services Interface XSS (cisco-sa-asaftd-xss-multiple-FCB3vPZe) (Direct Check)	Nessus	CISCO	medium
150997	Cisco Firepower Threat Defense Software Web Services Interface Multiple Vulnerabilities (cisco-sa-asaftd-xss-multiple-FCB3vPZe)	Nessus	CISCO	medium
150996	Cisco Adaptive Security Appliance Software Multiple Vulnerabilities (cisco-sa-asaftd-xss-multiple-FCB3vPZe)	Nessus	CISCO	medium

Detections

Analytics

CVE-2020-3580

medium

Tenable Plugins

medium

medium

medium