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Mallory
Medium

Arbitrary file write as root via path traversal in Cisco Secure Firewall FMC/FTD sftunnel file synchronization

IdentifiersCVE-2026-20018CWE-22

A vulnerability in the sftunnel functionality of Cisco Secure Firewall Management Center (FMC) Software and Cisco Secure Firewall Threat Defense (FTD) Software allows an authenticated remote attacker with administrative privileges to write arbitrary files as root on the underlying operating system. The issue is caused by insufficient validation of the directory path used during file synchronization, enabling a crafted directory path to escape the expected file location and result in creation or replacement of arbitrary files on the host OS.

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ANALYST BRIEF

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Impact

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Successful exploitation allows an authenticated admin-level attacker to create or replace arbitrary files on the underlying operating system with root privileges, which can lead to full system compromise (e.g., overwriting system configuration, planting malicious binaries/scripts, or modifying security-relevant files).

Mitigation

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Information currently not available in the provided content (no workaround/mitigation guidance included).

Remediation

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PUBLIC EXPLOITS

Exploits

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VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

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Threat actor evidence

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Associated malware

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Detection signatures

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Vendor-by-vendor mapping

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Social activity1

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