Cisco Catalyst SD-WAN Controller Authentication Bypass Vulnerability
cisco-sa-sdwan-rpa-EHchtZk
Summary
A vulnerability in the web interface of Cisco Secure Firewall Management Center (FMC) Software could allow an unauthenticated, remote attacker to log in to an affected device using a low-privileged account to access sensitive data within the impacted systems. This vulnerability is due to the presence of static user credentials for a low-privileged account. An attacker could exploit this vulnerability by using the account to log in to an affected system.
A successful exploit could allow the attacker to log in to the affected system and access sensitive data as the low-privileged user. Note: If the FMC management interface does not have public internet access, the attack surface that is associated with this vulnerability is reduced. Cisco has assigned this security advisory a Security Impact Rating (SIR) of High rather than Medium as the score indicates.
The reason is that this vulnerability can be used with other Cisco Secure FMC Software vulnerabilities to elevate privileges. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.
This advisory is part of a group of advisories. For a complete list of the advisories and links to them, see Cisco Advance Notification for Publication of September 16, 2026, Security Advisories.
In addition, for further documentation of improvements and fixes in Cisco Secure Firewall products, see Cisco Secure Firewall Adaptive Security Appliance Software, Secure Firewall Threat Defense Software, and Secure Firewall Management Center Software Hardening Release: September 2026. Security Impact Rating: High CVE: CVE-2026-20316
Products covered
A separate affected-products list was not included in the collected bulletin.
Remediation
Cisco has released software updates that address this vulnerability.
CVEs in this advisory 1
Update history
What changed in later vendor updates
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Updates
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