CVE-2026-20316 Cisco Secure Firewall Management Center (FMC): login or permission bypass
In plain words: A door that should be locked is not: part of the system can be reached without a valid login or permission. The attacker gets in as a user or administrator without knowing a password.
Confirmed exploited by CISA on · US federal patch deadline Aug 1, 2026
What to do
- Install Cisco's security update for Secure Firewall Management Center (FMC). If no update exists, follow the vendor's workaround or stop using the product until one ships.
- Patch edge devices first — attackers often start scanning for them within hours of a fix.
- Never expose the device's admin page to the internet.
- After patching a device that was exposed, follow the vendor's compromise checks, end active sessions and change passwords.
Who is affected
Work IT. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.
What's at risk: They face the internet and guard the whole network, so a flaw here can hand attackers a way in — and these devices usually run no antivirus, so break-ins go unnoticed.
The details
- Official name
- Cisco Secure Firewall Management Center Use of Hard-coded Password Vulnerability
- Product
- Cisco Secure Firewall Management Center (FMC)
- CISA description
- Cisco Secure Firewall Management Center (FMC) formerly known as Firepower Management Center contains a use of hard-coded password vulnerability that could allow an unauthenticated, remote attacker to log in to an affected device using a low-privileged account to access sensitive data within the impacted systems.
- Type of flaw
- Login or permission bypass (CWE-259)
- Confirmed exploited
- Jul 29, 2026 — known to be used in ransomware attacks
- US federal patch deadline
- Aug 1, 2026
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Answering about CVE-2026-20316 ·
Questions about CVE-2026-20316
Is CVE-2026-20316 being exploited?
Yes. CISA added CVE-2026-20316 to its Known Exploited Vulnerabilities catalog on Jul 29, 2026, which means there is reliable evidence of real-world attacks, including by ransomware groups.
How do I fix CVE-2026-20316?
Install Cisco's security update for Secure Firewall Management Center (FMC). If no update exists, follow the vendor's workaround or stop using the product until one ships. Patch edge devices first — attackers often start scanning for them within hours of a fix.
Am I affected by CVE-2026-20316?
Only if you use Cisco Secure Firewall Management Center (FMC). Aimed mostly at company systems — you are affected through the companies you use, not your own phone.