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Cisco fixed actively exploited Unified Communications zero day

Security Affairs
Actively Exploited
CVEZero-dayCiscoExploitVulnerabilityRCECriticalPatch

Overview

Cisco has addressed a serious security flaw in its Unified Communications and Webex Calling platforms, identified as CVE-2026-20045. This vulnerability allows attackers to execute arbitrary commands remotely without authentication, posing a significant risk to users. The flaw has been actively exploited in the wild, which raises concerns for organizations relying on these communication tools. With a CVSS score of 8.2, it is classified as critical, emphasizing the urgency for users to apply the available patches. Companies utilizing Cisco's services should prioritize updating their systems to mitigate potential attacks.

Key Takeaways

  • Active Exploitation: This vulnerability is being actively exploited by attackers. Immediate action is recommended.
  • Affected Systems: Cisco Unified Communications, Cisco Webex Calling
  • Action Required: Cisco has released patches to address the vulnerability.
  • Timeline: Newly disclosed

Original Article Summary

Cisco patched a critical zero-day RCE flaw (CVE-2026-20045) in Unified Communications and Webex Calling that is actively exploited in the wild. Cisco patched a critical zero-day remote code execution flaw, tracked as CVE-2026-20045 (CVSS score of 8.2), actively exploited in attacks. An unauthenticated, remote attacker can exploit the flaw to execute arbitrary commands on the […]

Impact

Cisco Unified Communications, Cisco Webex Calling

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 the vulnerability. Users should update their systems to the latest versions as soon as possible to protect against exploitation.

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 5 more.

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