CVE-2025-54658: Fortinet FortiDLP Path Traversal Flaw

CVE-2025-54658 Overview

CVE-2025-54658 is a path traversal vulnerability [CWE-22] in the Fortinet FortiDLP Agent's Outlookproxy plugin for macOS. An authenticated local attacker can send a crafted request to a local listening port and escalate privileges to root. The flaw affects multiple FortiDLP Agent release branches from 10.3.1 through 11.5.1. Fortinet published the issue in advisory FG-IR-25-628 on October 16, 2025.

Critical Impact
Successful exploitation grants root-level code execution on affected macOS endpoints, providing complete host compromise from a low-privileged local account.

Affected Products

Fortinet FortiDLP Agent versions 11.5.1, 11.4.2–11.4.6, 11.3.2–11.3.4, 11.2.0–11.2.3, 11.1.1–11.1.2, 11.0.1, 10.5.1, 10.4.0, and 10.3.1
Apple macOS endpoints running the affected agent versions
The Outlookproxy plugin component of the FortiDLP Agent

Discovery Timeline

2025-10-16 - CVE-2025-54658 published to NVD and disclosed in Fortinet advisory FG-IR-25-628
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-54658

Vulnerability Analysis

The Outlookproxy plugin inside the FortiDLP Agent exposes a local listening port on macOS hosts. The plugin runs with elevated privileges to intercept and inspect Outlook traffic for data loss prevention purposes. Requests arriving on this local port are parsed and used to construct file system paths without adequate validation of directory traversal sequences.

An authenticated local attacker can craft a request containing path traversal payloads such as ../ sequences. Because the receiving process operates as root, the resulting file operations execute with root privileges. This provides a direct path from a standard user context to full administrative control of the endpoint.

Root Cause

The root cause is improper limitation of a pathname to a restricted directory [CWE-22]. The Outlookproxy plugin accepts pathname components supplied over a local IPC channel and passes them to privileged file system operations without canonicalizing input or enforcing a directory allowlist. The absence of boundary checks allows the constructed path to escape the intended working directory.

Attack Vector

Exploitation requires local access and low-privileged authenticated credentials on the target macOS host. The attacker connects to the local port bound by the Outlookproxy plugin and issues a crafted request containing a traversal-laden path. No user interaction is required. The privileged plugin process then performs file operations outside its intended scope, which the attacker leverages to gain root execution.

No public proof-of-concept exploit has been observed, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog.

Detection Methods for CVE-2025-54658

Indicators of Compromise

Unexpected connections from non-Outlook processes to the local port bound by the FortiDLP Outlookproxy plugin
File writes or modifications outside the FortiDLP Agent working directories performed by the agent's privileged process
New root-owned files, launch daemons, or LaunchAgents created shortly after Outlookproxy plugin activity
Anomalous child processes spawned by the FortiDLP Agent running as root

Detection Strategies

Monitor macOS Endpoint Security Framework events for file operations by the FortiDLP Agent that target paths outside its installation directory
Baseline the Outlookproxy plugin's normal local port clients and alert on connections from unexpected user sessions or binaries
Correlate FortiDLP Agent process activity with subsequent privilege changes, cron entries, or persistence artifacts

Monitoring Recommendations

Enable verbose FortiDLP Agent logging on macOS fleets and forward logs to a centralized analytics platform
Alert on any local socket traffic to the Outlookproxy port originating from shells, scripting interpreters, or user-installed binaries
Track version inventory of FortiDLP Agent across the fleet to identify unpatched hosts

How to Mitigate CVE-2025-54658

Immediate Actions Required

Upgrade FortiDLP Agent on macOS to a fixed release as specified in Fortinet advisory FG-IR-25-628
Inventory all macOS endpoints running affected versions in the 10.3.x through 11.5.x ranges and prioritize patching
Restrict local user access on macOS hosts running FortiDLP Agent to reduce the pool of accounts able to reach the local port
Review recent agent logs for unexpected requests to the Outlookproxy plugin

Patch Information

Fortinet documents fixed versions and remediation guidance in the Fortinet Security Advisory FG-IR-25-628. Administrators should upgrade to the vendor-specified fixed releases for each affected branch. Deploy patches through managed device management tooling to ensure coverage across the fleet.

Workarounds

Disable the Outlookproxy plugin on affected macOS endpoints if the DLP feature it provides is not required, until patching is complete
Enforce macOS local firewall rules or application-layer controls to limit which processes may connect to the plugin's local port
Remove unnecessary local user accounts and enforce least privilege on shared macOS systems to reduce the authenticated attacker surface

bash

# Verify installed FortiDLP Agent version on macOS
/Applications/FortiDLPAgent.app/Contents/MacOS/FortiDLPAgent --version

# List local listeners to confirm Outlookproxy plugin binding
sudo lsof -iTCP -sTCP:LISTEN -n -P | grep -i outlook