CVE-2026-20340
published 2026-09-16CVE-2026-20340: A vulnerability in Cisco Secure FMC Software could allow an authenticated, remote attacker to execute arbitrary commands at the root privilege level. This…
PriorityP268high8.8CVSS 3.1
AVNACLPRLUINSUCHIHAH
EPSS
0.69%
52.0th percentile
A vulnerability in Cisco Secure FMC Software could allow an authenticated, remote attacker to execute arbitrary commands at the root privilege level.
This vulnerability is due to unsecured deserialization of web-management user-controlled data. An attacker could exploit this vulnerability by authenticating to the device and sending a crafted HTTP payload. A successful exploit could allow the attacker to save the crafted payload and then execute it on the underlying operating system as root.
To exploit this vulnerability, the attacker must have valid credentials for a user account with at least the role of Security Analyst (read-only).
Affected
68 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
| cisco | cisco_secure_firewall_management_center | — | — |
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VulDB
Cisco Secure Firewall Management Center up to 10.0.1 deserialization
vuldb·2026-09-16·CVSS 8.8
CVE-2026-20340 [HIGH] Cisco Secure Firewall Management Center up to 10.0.1 deserialization
A vulnerability marked as very critical has been reported in Cisco Secure Firewall Management Center. Affected is an unknown function. This manipulation causes deserialization.
This vulnerability is tracked as CVE-2026-20340. The attack is possible to be carried out remotely. No exploit exists.
It is suggested to upgrade the affected component.
GHSA
A vulnerability in Cisco Secure FMC Software could allow an authenticated, remote attacker to execute arbitrary commands at the root privilege level.
ghsa_unreviewed·2026-09-16
CVE-2026-20340 [HIGH] CWE-502 A vulnerability in Cisco Secure FMC Software could allow an authenticated, remote attacker to execute arbitrary commands at the root privilege level.
A vulnerability in Cisco Secure FMC Software could allow an authenticated, remote attacker to execute arbitrary commands at the root privilege level.
This vulnerability is due to unsecured deserialization of web-management user-controlled data. An attacker could exploit this vulnerability by authenticating to the device and sending a crafted HTTP payload. A successful exploit could allow the attacker to save the crafted payload and then execute it on the underlying operating system as root.
To exploit this vulnerability, the attacker must have valid credentials for a user account with at least the role of Security Analyst (read-only).
No detection rules found.
No public exploits indexed.
2026-09-16
Published