Critical

CISA Flags Exploited Cisco, Citrix, Fortinet Flaws, Sets Sept. 12 Federal Patch Deadline

The Hacker News

September 10, 2026 at 10:36 AM

Actively Exploited

Overview

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has identified three serious vulnerabilities affecting products from Cisco, Citrix, and Fortinet. These vulnerabilities have been added to CISA's Known Exploited Vulnerabilities catalog, which means federal agencies are required to patch them by September 12, 2026. One of the vulnerabilities, CVE-2026-20079, has a maximum severity score of 10.0, indicating a critical risk. It's crucial for organizations using these products to prioritize these updates to protect against potential exploitation. Failure to address these vulnerabilities could lead to significant security breaches, putting sensitive data at risk.

Key Takeaways

Active Exploitation: This vulnerability is being actively exploited by attackers. Immediate action is recommended.
Affected Systems: Cisco products, Citrix products, Fortinet products
Action Required: Federal Civilian Executive Branch agencies must apply patches by September 12, 2026.
Timeline: Disclosed on September 12, 2026

Original Article Summary

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) on Wednesday added three flaws, each impacting Cisco, Citrix, and Fortinet, to its Known Exploited Vulnerabilities (KEV) catalog, requiring Federal Civilian Executive Branch (FCEB) agencies to apply the patches by September 12, 2026. The vulnerabilities are listed below - CVE-2026-20079 (CVSS score: 10.0) - An authentication

Impact

Cisco products, Citrix products, Fortinet products

Exploitation Status

This vulnerability is confirmed to be actively exploited by attackers in real-world attacks. Organizations should prioritize patching or implementing workarounds immediately.

Timeline

Disclosed on September 12, 2026

Remediation

Federal Civilian Executive Branch agencies must apply patches by September 12, 2026. Specific patch numbers or versions were not mentioned.

Additional Information

This threat intelligence is aggregated from trusted cybersecurity sources. For the most up-to-date information, technical details, and official vendor guidance, please refer to the original article linked below.

Related Topics: This incident relates to CVE, Cisco, Fortinet, and 2 more.

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