Summary
| Parameter | Value |
|---|---|
| CVE ID | CVE-2026-20131 |
| Alert Source | CISA KEV - Active Exploitation |
| CVE Publication Year | 2026 |
| Date Published | 2026-03-19 |
| Vendor | Cisco |
| Product | Secure Firewall Management Center (FMC) |
| CVSS Score | 10.0 (critical) |
| EPSS Score | 0.6% (percentile: 68%) |
| CISA KEV | Yes - confirmed active exploitation |
| Ransomware | Yes - used in ransomware campaigns |
| Remediation Deadline | 2026-03-22 |
Vulnerability Description
Cisco Secure Firewall Management Center (FMC) Software and Cisco Security Cloud Control (SCC) Firewall Management contain a deserialization of untrusted data vulnerability in the web-based management interface that could allow an unauthenticated, remote attacker to execute arbitrary Java code as root on an affected device.
Required Actions
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Ransomware Warning
This vulnerability is actively exploited in ransomware campaigns. Immediate action is critical for your organization’s security.
Who Is Affected?
This vulnerability affects Secure Firewall Management Center (FMC) by Cisco. Check if your organization uses this software and requires updates.
Sources
Need help securing your systems? nFlo team offers vulnerability management and 24/7 SOC services. Contact us.
How can nFlo help?
If your organization uses products affected by this vulnerability, contact us. We can help with:
- Verifying whether your systems are at risk
- Implementing patches and risk mitigation
- Monitoring for exploitation attempts in your environment
Useful resources:
