Cisco Secure Firewall Management Center (FMC) and Security Cloud Control (SCC) Firewall Management
CVE-2026-20079
Cisco Secure Firewall Management Center (FMC) Software and Cisco Security Cloud Control (SCC) Firewall Management contain an authentication Bypass using an alternate path or channel vulnerability that could allow an unauthenticated, remote attacker to bypass authentication and execute script files on an affected device to obtain root access to the underlying operating system.
What this means for your business
- It affects Cisco Secure Firewall Management Center (FMC) and Security Cloud Control (SCC) Firewall Management. It matters if your company, or a supplier that handles your data, runs it.
- Attackers are already using it. CISA added it to its list of flaws used in real attacks on 9 September 2026.
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 76% chance of attack attempts being seen in the next 30 days, ranking above 99% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Cisco Secure Firewall Management Center (FMC) and Security Cloud Control (SCC) Firewall Management, and which version. The affected versions are listed further down this page.
- 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.
- 3Treat it as urgent. US federal agencies must fix it by 12 September 2026. That deadline does not apply to private companies, but it shows how seriously CISA takes it.
- 4Because attackers have used it, check the affected systems for signs of a break-in, not only for the update.
Not sure if your company is exposed?
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Required action
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
CISA’s wording, unedited. The notes it mentions are in CISA’s catalogue entry.
Scoring
- CVSS
- 10.0 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H- Weakness
- CWE-288
- Assigned by
- psirt@cisco.com
Dates
- Published
- 2026-09-09
- Last modified
- 2026-09-10
- Added to KEV
- 2026-09-09
- Remediation due
- 2026-09-12
- Sources
- CISA KEV, NVD
Affected products
- Cisco Secure Firewall Management Center7.0.0, 7.0.0.1, 7.0.1, 7.0.1.1, 7.0.2, 7.0.2.1, 7.0.3, 7.0.4, 7.0.5, 7.0.6, 7.0.6.1, 7.0.6.2, 7.0.6.3, 7.0.7, 7.0.8, 7.0.8.1, 7.0.9, 7.1.0, 7.1.0.1, 7.1.0.2, 7.1.0.3, 7.2.0, 7.2.0.1, 7.2.1, 7.2.2, 7.2.3, 7.2.3.1, 7.2.4, 7.2.4.1, 7.2.5, 7.2.5.1, 7.2.5.2, 7.2.6, 7.2.7, 7.2.8, 7.2.8.1, 7.2.9, 7.2.10, 7.2.10.1, 7.2.10.2, 7.2.11, 7.3.0, 7.3.1, 7.3.1.1, 7.3.1.2, 7.4.0, 7.4.1, 7.4.1.1, 7.4.2, 7.4.2.1, 7.4.2.2, 7.4.2.3, 7.4.2.4, 7.4.3, 7.4.4, 7.4.5, 7.4.6, 7.4.7, 7.6.0, 7.6.1, 7.6.2, 7.6.2.1, 7.6.3, 7.6.4, 7.6.5, 7.7.0, 7.7.10, 7.7.10.1, 7.7.11, 7.7.12, 10.0.0, 10.0.1
As listed in the NVD configuration data. Not a statement about your estate.
Coverage
- Cisco FMC Flaws Exploited to Steal Credentials and Deploy Qilin RansomwareThe Hacker News · 2026-09-11
- Cisco FMC bugs exploited by nation-state and ransomware actors (CVE-2026-20079, CVE-2026-20316)Help Net Security · 2026-09-10
- CISA Flags Exploited Cisco, Citrix, Fortinet Flaws, Sets Sept. 12 Federal Patch DeadlineThe Hacker News · 2026-09-10
- Organizations Warned of Cisco Secure FMC ExploitationSecurityWeek · 2026-09-10
- Cisco confirms CVE-2026-20079 Secure FMC flaw exploited in attacksBleepingComputer · 2026-09-09
- Cisco security advisory (AV26-197) – Update 3Canadian Centre for Cyber Security · 2026-09-09
References
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-onprem-fmc-authbypass-5JPp45V2
- http://seclists.org/fulldisclosure/2026/Aug/80
- https://blog.talosintelligence.com/fmc-ongoing-exploitation/
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20079