CVE-2021-41738 : Security Advisory and Response

ZeroShell 3.9.5 has a command injection vulnerability in /cgi-bin/kerbynet IP parameter, which may allow an authenticated attacker to execute system commands.

Understanding CVE-2021-41738

ZeroShell 3.9.5 is vulnerable to command injection, potentially enabling attackers to run unauthorized system commands.

What is CVE-2021-41738?

The CVE-2021-41738 vulnerability involves a command injection issue in ZeroShell's /cgi-bin/kerbynet IP parameter, which, if exploited, permits authenticated attackers to execute arbitrary system commands.

The Impact of CVE-2021-41738

The vulnerability poses a significant risk as it allows malicious actors to gain unauthorized access and execute commands on the affected system, potentially leading to data theft, service disruption, or further compromise.

Technical Details of CVE-2021-41738

ZeroShell 3.9.5's command injection vulnerability requires understanding specific technical aspects to address and mitigate the issue.

Vulnerability Description

The flaw lies in the handling of the IP parameter within the /cgi-bin/kerbynet directory, enabling attackers to inject and execute commands beyond the scope of their privileges.

Affected Systems and Versions

Product: ZeroShell
Version: 3.9.5
Status: Affected

Exploitation Mechanism

Attackers can exploit this vulnerability by injecting malicious commands into the IP parameter, leveraging authenticated access to execute unauthorized actions on the system.

Mitigation and Prevention

Effective mitigation strategies are crucial to safeguard systems against the CVE-2021-41738 vulnerability.

Immediate Steps to Take

Disable or restrict access to the vulnerable /cgi-bin/kerbynet directory.
Monitor for any suspicious activities or command injections related to the IP parameter.
Apply security updates or patches provided by ZeroShell promptly.

Long-Term Security Practices

Implement a robust access control mechanism to limit user privileges and prevent unauthorized command execution.
Conduct regular security audits and penetration testing to detect and remediate vulnerabilities proactively.

Patching and Updates

Stay informed about security advisories from ZeroShell and promptly apply patches or updates to address known vulnerabilities and improve overall system security.