Critical

CISA Orders Federal Agencies to Patch Exploited Plex2Shell, Siemens, and SiteGuard Flaws

The Hacker News

October 21, 2026 at 7:26 AM

Actively Exploited

Overview

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has officially added four vulnerabilities to its Known Exploited Vulnerabilities catalog, which includes significant flaws in the Plex Media Server, collectively referred to as Plex2Shell. One of these vulnerabilities, CVE-2026-96652, involves a server-side request forgery (SSRF) issue with a CVSS score of 5.3. This vulnerability could allow unauthorized access to sensitive information or systems, posing risks for users of Plex Media Server. CISA's action highlights the importance of addressing these security gaps to prevent potential exploitation. Federal agencies are urged to patch these vulnerabilities promptly to safeguard their systems and data.

Key Takeaways

Active Exploitation: This vulnerability is being actively exploited by attackers. Immediate action is recommended.
Affected Systems: Plex Media Server (various versions), Siemens products, SiteGuard systems
Action Required: CISA recommends that users of Plex Media Server apply the latest patches provided by Plex to mitigate the SSRF vulnerability.
Timeline: Newly disclosed

Original Article Summary

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) on Tuesday added four vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog, including four vulnerabilities impacting Plex Media Server that's collectively called Plex2Shell. The vulnerabilities are listed below - CVE-2026-96652 (CVSS score: 5.3) - Plex Media Server Server-Side Request Forgery (SSRF)

Impact

Plex Media Server (various versions), Siemens products, SiteGuard systems

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

CISA recommends that users of Plex Media Server apply the latest patches provided by Plex to mitigate the SSRF vulnerability. Specific patch numbers and versions were not detailed in the article, so users should check for updates directly from Plex's official channels.

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, Vulnerability, Patch.

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