Vulnerability record · CVE-2026-76420 · published 16 September 2026
CVE-2026-76420: Improper authorization 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.
Description
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.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
References
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2026-76420), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.