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Critical Cisco Secure Email Gateway and PAN-OS Flaws Expose Perimeter Devices

perimeter-device-exposurewidely-deployed-product-advisoryactively-exploited-vulnerabilityproof-of-concept-releaseend-of-life-software
Updated April 27, 2026 at 10:01 AM3 sources
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Critical Cisco Secure Email Gateway and PAN-OS Flaws Expose Perimeter Devices

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Cisco disclosed a critical vulnerability in Secure Email Gateway appliances running affected AsyncOS versions when inbound mail rules use File Analysis (Cisco AMP) or Content Filter features and the bundled Content Scanner Tools are older than 23.3.0.4823. Successful exploitation can let an attacker overwrite files at the operating-system level, enabling root-level account creation, configuration changes, arbitrary code execution, and denial of service. Cisco released software updates and said no alternative mitigations are available.

Palo Alto Networks also issued fixes for a serious PAN-OS management interface flaw that allows an unauthenticated attacker to execute certain PHP scripts and affect the integrity and confidentiality of the firewall, though the vendor said it does not permit arbitrary remote code execution. Exploitation attempts have already been observed and proof-of-concept code is public, increasing urgency for exposed management interfaces. Palo Alto said Cloud NGFW and Prisma Access are not affected, while PAN-OS 11.0 is out of support and will not receive a patch.

Timeline

  1. Feb 14, 2025

    Exploitation and PoC reported for PAN-OS vulnerability

    By the time of disclosure, exploitation attempts against the PAN-OS vulnerability had already been observed and proof-of-concept code had been published. Organizations were urged to update immediately and apply Palo Alto's mitigation guidance.

  2. Feb 14, 2025

    Palo Alto releases PAN-OS updates for management interface flaw

    Palo Alto Networks released security updates for a serious PAN-OS vulnerability affecting firewall management interfaces. The flaw allows an unauthenticated attacker to execute certain PHP scripts and could impact the integrity and confidentiality of PAN-OS; PAN-OS 11.0 is out of support and will not receive a fix.

  3. Jul 18, 2024

    Cisco fixes critical Secure Email Gateway file overwrite flaw

    Cisco released a software update for a critical vulnerability in Cisco Secure Email Gateway affecting vulnerable Cisco AsyncOS deployments with specific email-processing features enabled and outdated Content Scanner Tools. Successful exploitation could allow arbitrary file overwrite, root-level user creation, configuration changes, code execution, or denial of service.

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Sources

February 14, 2025 at 12:00 AM
July 18, 2024 at 12:00 AM
July 18, 2024 at 12:00 AM

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