Critical

Mandiant reveals how Cisco SD-WAN zero-day attacks gained root access

BleepingComputer

June 24, 2026 at 9:29 PM

Actively Exploited

Overview

Mandiant has reported on a serious vulnerability in Cisco's Catalyst SD-WAN, identified as CVE-2026-20245, which has been exploited by hackers to gain root access to affected devices. This zero-day attack allows attackers to create unauthorized root accounts, compromising network security for organizations using this technology. The vulnerability poses a significant risk to businesses relying on Cisco's SD-WAN solutions, as it can lead to unauthorized access and potential data breaches. Companies should urgently assess their systems for this vulnerability and implement necessary security measures to protect their networks.

Key Takeaways

Active Exploitation: This vulnerability is being actively exploited by attackers. Immediate action is recommended.
Affected Systems: Cisco Catalyst SD-WAN devices, specifically vulnerable versions of the Cisco SD-WAN software.
Action Required: Cisco has advised users to apply security patches as they become available.
Timeline: Newly disclosed

Original Article Summary

New details have been revealed on how hackers exploited a Cisco Catalyst SD-WAN vulnerability tracked as CVE-2026-20245 in zero-day attacks to create rogue root accounts on targeted devices. [...]

Impact

Cisco Catalyst SD-WAN devices, specifically vulnerable versions of the Cisco SD-WAN software.

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 advised users to apply security patches as they become available. Users should also review their configurations and access controls to ensure no unauthorized accounts exist. Additionally, monitoring for unusual activity on their networks is recommended.

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 1 more.

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