CVE-2026-20079

Cisco Secure Firewall Management Center (FMC) and Security Cloud Control (SCC) Firewall Management: Firewall Management Center Authentication Bypass Using an Alternate Path or Channel

As of , CVE-2026-20079 in Cisco Secure Firewall Management Center (FMC) and Security Cloud Control (SCC) Firewall Management is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch now.

Exploited
Yes: CISA listed it on 9 September 2026
US federal deadline
12 September 20263 days after CISA listed it. US federal civilian agencies must fix it by then.
Used in ransomware campaigns
Not known to CISA
Forensic triage
Required by CISA under BOD 26-04Agencies must also look for signs that attackers already got in.
EPSS score
0.88Higher than 99% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
Public exploit
1 Metasploit module
Fix
Vendor advice: sec.cloudapps.cisco.comLinks below, from CISA's entry.

What CISA says to do

Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

CISA's required action

What the flaw is

Cisco Secure Firewall Management Center (FMC) Software and Cisco Security Cloud Control (SCC) Firewall Management contain an authentication Bypass using an alternate path or channel vulnerability that could allow an unauthenticated, remote attacker to bypass authentication and execute script files on an affected device to obtain root access to the underlying operating system.

CISA's description

A vulnerability in the web interface of Cisco Secure Firewall Management Center (FMC) Software could allow an unauthenticated, remote attacker to bypass authentication and execute script files on an affected device to obtain root access to the underlying operating system.  This vulnerability is due to an improper system process that is created at boot time. An attacker could exploit this vulnerability by sending crafted HTTP requests to an affected device. A successful exploit could allow the attacker to execute a variety of scripts and commands that allow root access to the device. 

The CVE record's description, from cisco

CVE published
4 March 2026
Assigned by
cisco
CVSS
10.0 Critical (CVSS 3.1, from the CNA)
CWE-288
Authentication Bypass Using an Alternate Path or Channel
CISA SSVC, exploitation
active
CISA SSVC, automatable
yes
CISA SSVC, technical impact
total

Timeline

  1. The CVE record was published.
  2. CISA added it to its list of exploited vulnerabilities.
  3. The US federal deadline to fix it.

Public exploits

Facts from Metasploit's module list and Exploit-DB's index; we never copy exploit code.

  • Metasploit: Cisco Secure Firewall Management Center Authentication Bypass RCEexploit module, rank normal

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