CVE-2026-20079
Cisco Secure Firewall Management Center Authentication Bypass Remote Code Execution Vulnerability
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
10.0
Cisco Secure Firewall Management Center Authentication Bypass Remote Code Execution Vulnerability
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.
- Record
CVE-2026-20079- CVSS 3.1
- 10.0 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-288
- Updated
- 2026-11-02
EUVDEUVD-2026-9438
10.0
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.
- Record
EUVD-2026-9438- CVSS 3.1
- 10.0 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-mv8w-c2qv-cgrg
10.0
A vulnerability in the web interface of Cisco Secure Firewall Management Center (FMC) Software...
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.
- Record
GHSA-mv8w-c2qv-cgrg- CVSS 3.1
- 10.0 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-288
- Updated
- 2026-11-02
CISA KEV No score
Cisco Firewall Management Center Authentication Bypass Using an Alternate Path or Channel Vulnerability
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.
- Record
CVE-2026-20079- Weakness
- CWE-288
- Updated
- 2026-11-02
NVD
10.0
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.
- Record
CVE-2026-20079- CVSS 3.1
- 10.0 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-288
- Updated
- 2026-11-02
Affected products
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| Metasploit | Cisco Secure Firewall Management Center Authentication Bypass RCE | 2026-03-04 |
| PoC in GitHub | 0xBlackash/CVE-2026-20079 | 2026-03-28 |
| PoC in GitHub | CyberAuth/CVE-2026-20079 | 2026-08-17 |
| PoC in GitHub | DiegoArias008/CVE-2026-20079-checker | 2026-09-13 |
| Nuclei | Cisco Secure Firewall Management Center - Authentication Bypass |
History
| Recorded | Changed | Sources |
|---|---|---|
| exploitation, exploits | ||
| first indexed | CVE List, EUVD, GitHub Advisories, CISA KEV, Metasploit, Nuclei, NVD, PoC in GitHub |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-20079 is a critical vulnerability (CVSS 10.0) in Cisco Secure Firewall Management Center (fmc), published March 4, 2026. CISA lists it as known to be exploited, since September 9, 2026. EUVD reports exploitation since September 9, 2026. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 88.7%, the 99th percentile. No source names a fixed version.
References
sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-onprem-fmc-authbypass-5JPp45V2
blog.talosintelligence.com/fmc-ongoing-exploitation
cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20079
seclists.org/fulldisclosure/2026/Aug/80
nvd.nist.gov/vuln/detail/CVE-2026-20079
github.com/advisories/GHSA-mv8w-c2qv-cgrg