Critical

Cisco Patches Firewall Zero-Day Exploited for DoS Attacks

SecurityWeek

August 12, 2026 at 5:10 AM

Actively Exploited

Overview

Cisco has issued a patch for a serious vulnerability identified as CVE-2026-20349, which affects its Secure Firewall ASA and FTD devices. This flaw can be exploited remotely without the need for authentication, allowing attackers to launch Denial of Service (DoS) attacks against the devices. The ability to target these firewalls without prior access poses a significant risk to organizations that rely on Cisco's security solutions. Users of affected devices are urged to apply the updates provided by Cisco promptly to mitigate potential exploitation. The urgency of this patch reflects the growing trend of vulnerabilities being targeted in the wild, emphasizing the need for vigilant cybersecurity practices.

Key Takeaways

Active Exploitation: This vulnerability is being actively exploited by attackers. Immediate action is recommended.
Affected Systems: Cisco Secure Firewall ASA and FTD devices
Action Required: Cisco has released patches to address CVE-2026-20349.
Timeline: Newly disclosed

Original Article Summary

CVE-2026-20349 can be exploited remotely without authentication against Secure Firewall ASA and FTD devices. The post Cisco Patches Firewall Zero-Day Exploited for DoS Attacks appeared first on SecurityWeek.

Impact

Cisco Secure Firewall ASA and FTD devices

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

Newly disclosed

Remediation

Cisco has released patches to address CVE-2026-20349. Users are advised to apply the latest updates to their Secure Firewall ASA and FTD devices to protect against potential DoS attacks.

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, Zero-day, Cisco, and 2 more.

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