CVE-2026-76420
Cisco Secure Firewall Management Center Software Impersonated sftunnel Connection Vulnerability
A vulnerability in the internal configuration of the Apache JServ Protocol (AJP) connector for Cisco Secure FMC Software could allow an unauthenticated, remote attacker to impersonate a peer device.
This vulnerability is due to incorrect initialization of encryption parameters for the AJP connector at boot time. An attacker could exploit this vulnerability by sending crafted packets to the AJP connector. A successful exploit could allow the attacker to execute commands as root and gain full control over the FMC REST APIs on the affected device. Note: This vulnerability can be exploited only if the valid sftunnel connection between Cisco Secure FMC Software and Cisco Secure FTD Software is down.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- 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
Cisco Secure Firewall Management Center Software Impersonated sftunnel Connection Vulnerability
A vulnerability in the internal configuration of the Apache JServ Protocol (AJP) connector for Cisco Secure FMC Software could allow an unauthenticated, remote attacker to impersonate a peer device.
This vulnerability is due to incorrect initialization of encryption parameters for the AJP connector at boot time. An attacker could exploit this vulnerability by sending crafted packets to the AJP connector. A successful exploit could allow the attacker to execute commands as root and gain full control over the FMC REST APIs on the affected device. Note: This vulnerability can be exploited only if the valid sftunnel connection between Cisco Secure FMC Software and Cisco Secure FTD Software is down.
- Record
CVE-2026-76420- CVSS 3.1
- 9.0 Critical
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-285
- Updated
- 2026-11-02
EUVDEUVD-2026-80887
A vulnerability in the internal configuration of the Apache JServ Protocol (AJP) connector for Cisco Secure FMC Software could allow an unauthenticated, remote attacker to impersonate a peer device.
This vulnerability is due to incorrect initialization of encryption parameters for the AJP connector at boot time. An attacker could exploit this vulnerability by sending crafted packets to the AJP connector. A successful exploit could allow the attacker to execute commands as root and gain full control over the FMC REST APIs on the affected device. Note: This vulnerability can be exploited only if the valid sftunnel connection between Cisco Secure FMC Software and Cisco Secure FTD Software is down.
- Record
EUVD-2026-80887- CVSS 3.1
- 9.0 Critical
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-4fw2-5j8h-69f2
A vulnerability in the internal configuration of the Apache JServ Protocol (AJP) connector...
A vulnerability in the internal configuration of the Apache JServ Protocol (AJP) connector for Cisco Secure FMC Software could allow an unauthenticated, remote attacker to impersonate a peer device.
This vulnerability is due to incorrect initialization of encryption parameters for the AJP connector at boot time. An attacker could exploit this vulnerability by sending crafted packets to the AJP connector. A successful exploit could allow the attacker to execute commands as root and gain full control over the FMC REST APIs on the affected device. Note: This vulnerability can be exploited only if the valid sftunnel connection between Cisco Secure FMC Software and Cisco Secure FTD Software is down.
- Record
GHSA-4fw2-5j8h-69f2- CVSS 3.1
- 9.0 Critical
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-285
- Updated
- 2026-11-02
NVD
A vulnerability in the internal configuration of the Apache JServ Protocol (AJP) connector for Cisco Secure FMC Software could allow an unauthenticated, remote attacker to impersonate a peer device.
This vulnerability is due to incorrect initialization of encryption parameters for the AJP connector at boot time. An attacker could exploit this vulnerability by sending crafted packets to the AJP connector. A successful exploit could allow the attacker to execute commands as root and gain full control over the FMC REST APIs on the affected device. Note: This vulnerability can be exploited only if the valid sftunnel connection between Cisco Secure FMC Software and Cisco Secure FTD Software is down.
- Record
CVE-2026-76420- CVSS 3.1
- 9.0 Critical
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-285
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-76420 is a critical vulnerability (CVSS 9.0) in Cisco Secure Firewall Management Center (fmc), published September 16, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.38%, the 31st percentile. No source names a fixed version.