CVE-2026-12602 Overview
CVE-2026-12602 is an incorrect default permissions vulnerability [CWE-276] in ArubaSign versions prior to v4.6.6. The software installer assigns excessive permissions to the Everyone group on its main executable and supporting files located under C:\Program Files. An unprivileged local user can replace the executable or its components with a malicious binary. When the replaced binary is later executed by a privileged user or a system service, the attacker gains code execution at that elevated context. This pattern is commonly abused for local privilege escalation to Administrator or SYSTEM.
Critical Impact
A local unprivileged user can overwrite ArubaSign program files and achieve arbitrary code execution, potentially escalating to Administrator or SYSTEM and gaining full control of the host.
Affected Products
- ArubaSign versions prior to v4.6.6
- Windows installations where ArubaSign deploys to C:\Program Files
- Systems where multiple users share an ArubaSign installation
Discovery Timeline
- 2026-06-22 - CVE-2026-12602 published to the National Vulnerability Database (NVD)
- 2026-06-22 - Last updated in NVD database
Technical Details for CVE-2026-12602
Vulnerability Analysis
The vulnerability stems from misconfigured Access Control Lists (ACLs) applied during installation. ArubaSign places its main executable and program components in C:\Program Files, a directory normally restricted to administrative write access. The installer overrides the default ACL inheritance and grants the Everyone group write or modify permissions on these files. Any user on the system can therefore replace trusted binaries with attacker-controlled code. The replacement persists until the binary is executed under a higher-privileged context, such as when an administrator launches ArubaSign or when a service or scheduled task invokes it.
Root Cause
The root cause is the assignment of inappropriate permissions during default installation, classified as Incorrect Default Permissions [CWE-276]. Rather than inheriting the restrictive ACL of C:\Program Files, ArubaSign files receive an explicit Discretionary Access Control List (DACL) entry granting modify rights to the Everyone group. This breaks the trust boundary that Windows enforces between standard users and protected program directories.
Attack Vector
The attack requires local access and some user interaction, but no prior privileges. An attacker with a standard user account enumerates C:\Program Files for files with weak ACLs. After identifying the ArubaSign executable, the attacker overwrites it with a malicious payload of the same name. When a higher-privileged user or process subsequently runs ArubaSign, the malicious payload executes in that context. This yields arbitrary code execution and, in the worst case, full privilege escalation to Administrator or SYSTEM.
No verified public proof-of-concept code is available. Refer to the INCIBE Security Notice for the official advisory.
Detection Methods for CVE-2026-12602
Indicators of Compromise
- Modification timestamps on files under C:\Program Files\ArubaSign\ that do not match the original installer manifest.
- Unsigned or untrusted binaries replacing the legitimate ArubaSign executable.
- ACL entries on ArubaSign program files granting Everyone write or modify permissions.
- Process executions originating from C:\Program Files\ArubaSign\ spawning unexpected child processes such as cmd.exe, powershell.exe, or network utilities.
Detection Strategies
- Audit ACLs on C:\Program Files\ArubaSign\* using icacls and flag entries that include Everyone:(M) or Everyone:(F).
- Monitor for file write events on ArubaSign binaries performed by non-administrative user accounts via Windows Security event ID 4663.
- Validate code-signing status of all ArubaSign executables and DLLs after installation and on a recurring schedule.
Monitoring Recommendations
- Enable Windows object access auditing on the ArubaSign installation directory to capture all write and modify operations.
- Generate alerts when standard user accounts modify files inside C:\Program Files subdirectories.
- Track parent-child process relationships where ArubaSign launches interpreters or shell processes inconsistent with normal usage.
How to Mitigate CVE-2026-12602
Immediate Actions Required
- Upgrade ArubaSign to version 4.6.6 or later on all affected Windows endpoints.
- Inventory all hosts running ArubaSign and prioritize multi-user systems and shared workstations.
- Restrict interactive logon on systems with vulnerable ArubaSign installations until patching is complete.
Patch Information
The vendor addressed the issue in ArubaSign v4.6.6 by correcting installer ACLs so that program files inherit the standard restrictive permissions of C:\Program Files. Consult the INCIBE Security Notice for vendor guidance and download links.
Workarounds
- Manually reset ACLs on the ArubaSign installation directory to remove write and modify permissions for the Everyone group.
- Apply the principle of least privilege by removing local administrative rights from standard user accounts on affected hosts.
- Use Group Policy to enforce restrictive directory permissions on C:\Program Files\ArubaSign\ across the fleet.
# Configuration example: remove Everyone group write access from ArubaSign directory
icacls "C:\Program Files\ArubaSign" /remove:g Everyone /T /C
icacls "C:\Program Files\ArubaSign" /inheritance:r /T /C
icacls "C:\Program Files\ArubaSign" /grant:r "Administrators:(OI)(CI)F" "SYSTEM:(OI)(CI)F" "Users:(OI)(CI)RX" /T /C
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
