Executive Summary

Researchers from Claroty's Team82 have disclosed a critical remote code execution (RCE) vulnerability, CVE-2025-12556, in the IDIS Cloud Manager (ICM) viewer. The vulnerability, which CISA has rated with a CVSS v4 score of 8.7, enables an attacker to achieve code execution on a host machine simply by tricking a user into clicking a malicious link. This type of '1-click RCE' is particularly dangerous as it can bypass the browser sandbox and provides a direct path to system compromise, making it highly attractive for use in targeted spear-phishing campaigns. IDIS has released an update, and users are strongly advised to upgrade to ICM viewer version 1.7.1 or uninstall the application.

Vulnerability Details

CVE-2025-12556 is an argument injection vulnerability within the custom URL handler used by the IDIS Cloud Manager viewer. When a user clicks a specially crafted link beginning with the idis-icm-viewer:// protocol, the browser passes the URL to the ICM viewer application. The application fails to properly sanitize the arguments passed in this URL.

An attacker can craft a URL that injects malicious commands or arguments. When the ICM viewer application processes this URL, it executes the injected code with the permissions of the host user. This allows the attacker to break out of the browser's security sandbox and execute arbitrary code on the underlying operating system.

Attack Vector: The user must be convinced to click a malicious link. This can be delivered via a phishing email, a deceptive website, or a chat message.

Technical Analysis

The vulnerability stems from a common flaw in applications that implement custom URL protocol handlers. These handlers are a convenient way to launch a local application from a web browser, but they become a security risk if they trust and execute input from the URL without rigorous validation.

In this case, an attacker could craft a link like: idis-icm-viewer://?argument=[malicious_command]

The ICM viewer application would parse this and execute [malicious_command] on the user's system. This could be used to launch PowerShell to download and run malware, for example.

MITRE ATT&CK TTPs

• Initial Access: T1566.002 - Phishing: Spearphishing Link
• Execution: T1204.002 - User Execution: Malicious File (While a link, the user's click causes execution on the host), T1203 - Exploitation for Client Execution
• Defense Evasion: T1218 - System Binary Proxy Execution (The injected command could use a legitimate system binary like mshta.exe or rundll32.exe to execute malware).

Impact Assessment

A successful exploit gives an attacker the ability to execute code with the same privileges as the user who clicked the link. The business impact is severe:

• Endpoint Compromise: The attacker can install malware, such as ransomware, spyware, or keyloggers, on the user's workstation.
• Lateral Movement: The compromised machine becomes a foothold within the corporate network, which the attacker can use to pivot to other systems.
• Data Theft: Sensitive data on the user's machine and accessible network shares can be stolen.
• Targeted Attacks: Since IDIS Cloud Manager is used for managing video surveillance systems, a successful attack could potentially lead to the compromise of physical security infrastructure, allowing an attacker to tamper with or disable surveillance cameras.

This '1-click' nature of the RCE makes it a low-effort, high-impact vulnerability for attackers.

Detection & Response

• Process Monitoring: Use an EDR to monitor for the ICM Viewer process spawning suspicious child processes like cmd.exe, powershell.exe, or other scripting engines. This is a primary indicator of exploitation.
• Network Analysis: Look for unusual outbound network connections from workstations immediately after a user browses the web. This could indicate malware downloaded via the exploit is calling back to its C2 server.
• Threat Hunting: Proactively hunt for executions of the ICM Viewer process with unusual command-line arguments. Enable process command-line logging (e.g., via Sysmon Event ID 1) to facilitate this.

Mitigation

1. Update or Uninstall: The most effective mitigation is to upgrade the IDIS Cloud Manager viewer to the patched version 1.7.1 immediately. If the software is not essential, uninstalling it completely removes the attack surface. This is a critical D3FEND Software Update.
2. User Training: Educate users about the dangers of clicking links from untrusted sources, even if they appear to be for legitimate applications used within the company. This aligns with M1017 - User Training.
3. Disable URL Protocol Handler (Advanced): As a temporary workaround if patching is not immediately possible, it may be possible to de-register the idis-icm-viewer:// protocol handler in the Windows Registry. This would prevent the vulnerability from being triggered from a browser but may break legitimate functionality. This should only be done by experienced administrators.