CVE-2025-10539: DeskTime Time Tracking App RCE Vulnerability

CVE-2025-10539 Overview

CVE-2025-10539 is an Improper Certificate Validation vulnerability (CWE-295) affecting the DeskTime Time Tracking App before version 1.3.674. Due to improper TLS certificate validation, attackers who can position themselves in the network path between the client and the DeskTime update servers can return a malicious executable in response to an update request. This allows the attacker to achieve user-level remote code execution on the affected client.

Critical Impact
This vulnerability enables man-in-the-middle attackers to deliver malicious executables during the application update process, potentially compromising systems running the vulnerable DeskTime client.

Affected Products

DeskTime Time Tracking App versions prior to 1.3.674

Discovery Timeline

2026-04-28 - CVE-2025-10539 published to NVD
2026-04-29 - Last updated in NVD database

Technical Details for CVE-2025-10539

Vulnerability Analysis

The vulnerability stems from the DeskTime Time Tracking App's failure to properly validate TLS certificates when communicating with update servers. When the application checks for or downloads updates, it does not verify that the server presenting the TLS certificate is the legitimate DeskTime update server. This creates an opportunity for attackers positioned on the network path to intercept these communications.

The attack requires the adversary to have network-level access between the victim's machine and the DeskTime update infrastructure. While this increases the attack complexity, scenarios such as compromised public Wi-Fi networks, malicious network proxies, or ARP spoofing on local networks make this attack vector practical in many real-world environments.

Root Cause

The root cause is improper TLS certificate validation (CWE-295) in the application's update mechanism. The application either fails to verify the certificate chain, does not check certificate validity, or improperly handles certificate errors during the HTTPS connection to update servers. This allows attackers to present their own certificates without triggering security warnings or connection failures.

Attack Vector

The attack follows a classic man-in-the-middle (MITM) pattern targeting the software update process:

The attacker positions themselves on the network path between the victim and DeskTime update servers (e.g., via ARP spoofing, rogue access point, or compromised network infrastructure)
When the DeskTime client initiates an update check or download, the attacker intercepts the request
The attacker responds with a malicious executable masquerading as a legitimate update
Due to missing certificate validation, the client accepts the response from the attacker
The malicious payload executes with the privileges of the current user, achieving remote code execution

The network-based attack vector with high complexity requirements reflects the need for the attacker to establish and maintain the MITM position during the update process.

Detection Methods for CVE-2025-10539

Indicators of Compromise

Unexpected network traffic from DeskTime application to non-standard IP addresses
Certificate warnings or anomalies in network traffic logs related to DeskTime update communications
Unusual executable files downloaded or executed by the DeskTime process
Modified or unexpected DeskTime binaries on client systems

Detection Strategies

Monitor for ARP spoofing or other MITM indicators on networks where DeskTime clients operate
Implement network traffic analysis to detect certificate anomalies in HTTPS connections to DeskTime servers
Use endpoint detection solutions to alert on unexpected child processes spawned by DeskTime applications
Review system logs for executable downloads from non-standard sources during DeskTime update windows

Monitoring Recommendations

Enable network-level TLS inspection to identify connections with certificate validation failures
Configure endpoint security tools to monitor the DeskTime application directory for unexpected binary modifications
Implement file integrity monitoring for DeskTime installation directories
Review DNS queries to identify potential redirection of update server domains

How to Mitigate CVE-2025-10539

Immediate Actions Required

Update DeskTime Time Tracking App to version 1.3.674 or later immediately
Avoid using the vulnerable DeskTime application on untrusted networks until patched
Implement network segmentation to reduce exposure to potential MITM attacks
Monitor systems running vulnerable versions for signs of compromise

Patch Information

The vulnerability has been addressed in DeskTime Time Tracking App version 1.3.674. Users should update to this version or later to remediate the vulnerability. The updated version is available from the DeskTime Download Page. For additional technical details about the vulnerability, refer to the SEC Consult Security Report and the SEC Consult RCE Advisory.

Workarounds

Restrict DeskTime application usage to trusted, secured network environments only
Implement network-level certificate pinning or TLS inspection at the perimeter to detect MITM attempts
Disable automatic updates and manually verify update integrity before installation
Use a VPN when operating on potentially hostile networks to reduce MITM exposure