CVE-2025-5296: Improper Link Resolution Privilege Escalation

CVE-2025-5296 Overview

CVE-2025-5296 is an improper link resolution before file access vulnerability [CWE-59] disclosed by Schneider Electric. A low-privileged local attacker can tamper with the installation folder and abuse symbolic link resolution to write arbitrary data to protected locations. Successful exploitation can lead to privilege escalation, arbitrary file corruption, exposure of application and system information, or persistent denial of service. Schneider Electric documented the issue in security notice SEVD-2025-224-03.

Critical Impact
A local, low-privileged user can escalate privileges and cause persistent denial of service by exploiting insecure link resolution against the affected installation directory.

Affected Products

Schneider Electric product referenced in advisory SEVD-2025-224-03
See vendor advisory for the complete affected version list
Deployments where non-administrative users have write access to the installation folder

Discovery Timeline

2025-08-18 - CVE-2025-5296 published to the National Vulnerability Database (NVD)
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-5296

Vulnerability Analysis

The flaw is a link-following weakness within the affected Schneider Electric product's installation directory. The application resolves file paths without validating whether they traverse symbolic links or junctions before performing privileged file operations. A local attacker with low privileges plants a link inside the installation folder that redirects a trusted process to a protected location. When the trusted process writes to the target, the write occurs under elevated context, corrupting files the attacker could not otherwise modify.

The attack requires local access and low privileges, with no user interaction. Confidentiality impact is limited, but integrity and availability impact are high, reflecting arbitrary file overwrite in protected locations.

Root Cause

The root cause is improper link resolution before file access [CWE-59]. The affected component does not canonicalize paths or verify link targets prior to opening files for write operations. Because the installation folder inherits permissions that allow low-privileged users to create files or links, an attacker can influence where privileged writes land.

Attack Vector

An attacker with a local user account and write access to the installation folder plants a symbolic link, hard link, or NTFS junction that redirects a legitimate file operation. When the vulnerable service, installer routine, or updater executes with higher privileges, it follows the attacker-controlled link and writes to files owned by SYSTEM or root. The attacker uses this primitive to overwrite binaries loaded by privileged processes, corrupt configuration files, or destroy data required for service startup.

No verified exploit code is publicly available. Refer to the Schneider Electric Security Notice SEVD-2025-224-03 for technical details.

Detection Methods for CVE-2025-5296

Indicators of Compromise

Creation of symbolic links, hard links, or junctions inside the affected product's installation directory by non-administrative accounts
Unexpected modification timestamps on files within protected system directories after execution of the affected product's services or updaters
New or altered executables and DLLs in the installation folder that do not match the vendor's signed baseline
Repeated service crashes or failed startups after low-privileged user activity on the host

Detection Strategies

Monitor filesystem events for CreateSymbolicLink, CreateHardLink, and reparse point creation within the Schneider Electric installation path
Alert on privileged processes writing to paths that resolve through user-writable directories
Baseline installation folder contents and flag deviations against the vendor-provided hashes
Correlate low-privileged process activity with subsequent SYSTEM-context file writes using endpoint telemetry

Monitoring Recommendations

Enable Windows object access auditing on the installation directory and downstream protected locations
Ingest filesystem, process, and service events into a centralized data lake for retrospective hunting
Track service restarts and crash events tied to the affected Schneider Electric product
Review scheduled tasks and update routines that operate on the installation folder under elevated privileges

How to Mitigate CVE-2025-5296

Immediate Actions Required

Apply the fixes described in Schneider Electric advisory SEVD-2025-224-03 as soon as they are available for your product version
Restrict write permissions on the installation directory to administrators only
Remove any existing symbolic links, junctions, or hard links from the installation path that were not created by the installer
Audit local accounts on affected hosts and remove unnecessary interactive login rights

Patch Information

Schneider Electric published remediation guidance in SEVD-2025-224-03. Consult the advisory for fixed versions, upgrade steps, and any product-specific hardening instructions.

Workarounds

Harden ACLs on the installation folder so only Administrators and SYSTEM retain write access
Disable non-essential local user accounts on hosts running the affected product
Where supported, disable symbolic link creation for non-administrative users via Group Policy (SeCreateSymbolicLinkPrivilege)
Isolate affected engineering workstations from general-purpose user environments until patched

bash

# Configuration example: restrict symlink creation and tighten installation folder ACLs on Windows
# Remove SeCreateSymbolicLinkPrivilege from non-admin users via secpol.msc or:
secedit /export /cfg C:\secpol.cfg
# Edit C:\secpol.cfg and set SeCreateSymbolicLinkPrivilege = *S-1-5-32-544
secedit /configure /db secedit.sdb /cfg C:\secpol.cfg /areas USER_RIGHTS

# Restrict write access on the installation folder to Administrators and SYSTEM
icacls "C:\Program Files\<VendorInstallPath>" /inheritance:r
icacls "C:\Program Files\<VendorInstallPath>" /grant:r "Administrators:(OI)(CI)F" "SYSTEM:(OI)(CI)F" "Users:(OI)(CI)RX"