CVE-2026-118477 in Kalifast
Summary
by MITRE • 10/28/2026
The ei_git_repo_url parameter in the Git remote configuration endpoint of KaliFast is vulnerable to OS Command Injection. This OS Command Injection vulnerability allows an authenticated attacker (free registration available) to execute arbitrary commands on the KaliFast server with www-data privileges. Fixed in version 2026061802.
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Analysis
by VulDB Data Team • 10/28/2026
The KaliFast application, a tool designed for automating the deployment of penetration testing environments such as Kali Linux virtual machines and containers, contains a critical security flaw within its Git remote configuration functionality. Specifically, the ei_git_repo_url parameter is susceptible to OS Command Injection when processed by the backend system responsible for managing repository configurations. This vulnerability arises because the application fails to adequately sanitize or validate user-supplied input before passing it to underlying operating system commands. In many web applications that interact with version control systems, developers may inadvertently concatenate user inputs directly into shell command strings without employing safe APIs or proper escaping mechanisms. When an attacker provides a maliciously crafted URL containing special characters such as semicolons, pipes, or ampersands followed by arbitrary shell commands, the backend interprets these not merely as part of a repository address but as executable instructions for the host operating system.
The operational impact of this vulnerability is severe due to the privilege level at which it operates. The KaliFast service typically runs with www-data privileges, which corresponds to the user account under which web servers like Apache or Nginx execute their worker processes. While this is a restricted non-root user on most Linux distributions, it still possesses significant capabilities within the context of the application and its immediate environment. An authenticated attacker can leverage this flaw to read sensitive configuration files located in directories accessible by www-data, such as database credentials stored in plain text or private keys used for SSH authentication. Furthermore, if the web server has write access to specific directories where scripts are executed, an attacker could potentially upload a malicious script and then trigger its execution via the command injection vector. This effectively grants the attacker full control over the compromised service instance, allowing them to pivot into other parts of the network or escalate privileges further by exploiting local kernel vulnerabilities if they exist on the host system.
From a classification perspective, this vulnerability aligns with CWE-78 Improper Neutralization of Special Elements used in an OS Command commonly known as OS Command Injection. The root cause is a failure to implement proper input validation and output encoding strategies for data that interacts directly with the operating system shell. In terms of offensive security frameworks, this behavior maps closely to MITRE ATT&CK technique T1059 Command and Scripting Interpreter, specifically sub-techniques involving direct OS command execution via web application interfaces. The vulnerability highlights a common oversight in development practices where convenience is prioritized over secure coding standards, particularly when integrating external tools like Git into automated workflows without rigorous security reviews of the integration points.
Mitigation strategies must address both immediate remediation and long-term architectural improvements. As indicated by the vendor, upgrading to version 2026061802 or later resolves this issue through code changes that likely involve strict input validation, parameterized command execution APIs, or sandboxing mechanisms for Git operations. For organizations unable to upgrade immediately, compensating controls should include implementing a Web Application Firewall with rules specifically tuned to detect and block common OS injection payloads such as backticks, dollar signs, and shell metacharacters within URL parameters. Additionally, restricting the www-data user's permissions through mandatory access control systems like SELinux or AppArmor can limit the blast radius of any successful exploitation by preventing access to sensitive files outside the application's designated working directory. Regular security audits focusing on input handling in all external-facing endpoints are essential to prevent similar vulnerabilities from being introduced during future development cycles.