Firewalls & VPN
CVE-2026-20336: Cisco ASA, FTD, and FMC hardening: Resource Lifetime Management Vulnerabilities
Cisco groups resource-lifetime flaws across ASA, FTD and FMC without describing an individual attack path. The article separates conflicting source scores and affected-hotfix guidance from an exploitation footnote belonging to another category.
CVE-2026-20340: Cisco Secure FMC Software Deserialization Arbitrary Root Command Execution Vulnerability
Even a read-only Security Analyst account can submit an FMC web-management payload that executes as root. Review those accounts and install the CVE-specific fixed release; a read-only application role does not remove this execution risk.
CVE-2026-20341: Cisco Secure FMC Software sftunnel Deserialization Root Command Execution Vulnerability
Privileged access on a managed FTD device can enable sftunnel deserialization attacks against FMC and its high-availability peer. Review managed-device trust and apply the specific fix, retaining Cisco's differing descriptions of the required privilege.
CVE-2026-20342: Cisco Secure FMC Software Arbitrary File Download Vulnerability
A Security Analyst or higher FMC account can retrieve arbitrary files through the download API. Apply the specific update and review download evidence; patching cannot retract files already obtained, and file writing is not established.
CVE-2026-20343: Cisco Secure FMC Software Information Disclosure and Disk DoS Vulnerability
Unauthenticated FMC API requests can expose sensitive files and consume disk space until the manager becomes unresponsive. Preserve request and file evidence before cleanup, then apply the fix and assess disclosure separately from service restoration.
CVE-2026-20344: Cisco Secure FMC Software SQL Injection Vulnerability
FMC Security Approver, Access Admin or Network Admin accounts can obtain database information and an Administrator's session credentials. Apply the CVE-specific fix and review these starting roles, not only full-administrator login activity.
CVE-2026-20295: Cisco Secure FMC Software and Secure FTD Software sftunnel Memory Exhaustion DoS Vulnerability
Crafted frames during sftunnel TLS setup can exhaust memory on vulnerable FMC and FTD devices. Inventory both ends of the management connection, preserve resource-pressure evidence, and install each platform's CVE-specific fixed release.
CVE-2026-20323: Cisco Secure FMC Software and Secure FTD Software sftunnel Unauthorized Authentication Bypass Vulnerability
An adjacent-network attacker can impersonate an sftunnel peer and obtain root-equivalent manager access while the legitimate tunnel is down or disrupted. Update FMC and FTD, preserving peer-registration and interruption evidence for separate investigation.
CVE-2026-20324: Cisco Secure Firewall Management Center sftunnel Root Arbitrary Code Execution Vulnerability
With valid credentials and a registered or hijacked sftunnel connection, an attacker can write a file that executes as root on FMC. Check peers and tunnel state, preserve evidence, and install the specific fix.
CVE-2026-20242: Cisco Secure Firewall Management Center Software Java Deserialization Remote Code Execution Vulnerability
An attacker controlling an allowed External Database Access host can execute root commands on vulnerable FMC software. Check the feature and host list, evaluate temporary disablement, and install the CVE-specific fixed release.