CVE-2026-42153 in Coolify
Summary
by MITRE • 07/07/2026
Coolify is an open-source and self-hostable tool for managing servers, applications, and databases. Prior to 4.0.0-beta.474, PostgreSQL healthcheck command generation used attacker-controlled database settings (postgres_user and postgres_db) in shell-form commands, allowing an authenticated user to inject commands executed in the database container. This issue is fixed in version 4.0.0-beta.474.
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Analysis
by VulDB Data Team • 07/07/2026
This vulnerability affects Coolify versions prior to 4.0.0-beta.474 and represents a critical command injection flaw in the PostgreSQL healthcheck functionality. The issue stems from improper input validation and sanitization within the database container command generation process, where user-controlled parameters are directly incorporated into shell-form commands without adequate escaping or filtering mechanisms.
The technical flaw manifests when Coolify generates healthcheck commands for PostgreSQL containers, specifically utilizing attacker-controlled values from postgres_user and postgres_db configuration settings. These parameters, intended for database authentication and selection, are concatenated directly into shell execution contexts without proper sanitization, creating a classic command injection vulnerability that allows malicious input to be interpreted as additional shell commands. This design pattern violates fundamental security principles and creates an attack surface where authenticated users can execute arbitrary code within the database container context.
The operational impact of this vulnerability is severe, as it enables authenticated attackers to escalate privileges and potentially compromise the entire database infrastructure. An attacker with legitimate access to Coolify's web interface could leverage this flaw to execute arbitrary commands on the host system running the database containers, potentially leading to data exfiltration, privilege escalation, or complete system compromise. The vulnerability affects the core container management functionality, making it particularly dangerous for environments where multiple users have access to the Coolify platform.
This issue maps directly to CWE-78, which describes improper neutralization of special elements used in OS commands, and aligns with ATT&CK technique T1059.004 for command and script injection. The vulnerability demonstrates poor input validation practices and highlights the critical importance of proper sanitization when building dynamic shell commands from user-provided data. Organizations using Coolify versions prior to 4.0.0-beta.474 should immediately implement mitigation strategies including disabling unnecessary database healthcheck functionality, restricting access to Coolify interfaces, and monitoring for suspicious command execution patterns within affected containers.
The fix implemented in version 4.0.0-beta.474 addresses this vulnerability by properly sanitizing and escaping the postgres_user and postgres_db parameters before incorporating them into shell commands. This update ensures that user input cannot be interpreted as additional shell instructions, effectively closing the command injection attack vector. Security teams should verify that all Coolify installations have been upgraded to the patched version and conduct thorough security assessments of any systems where this vulnerability may have been exploited.
Organizations relying on self-hosted infrastructure tools like Coolify must maintain strict security practices around input validation and command construction, particularly in containerized environments where privilege escalation risks are heightened. The vulnerability serves as a reminder that seemingly benign configuration parameters can create dangerous attack surfaces when not properly sanitized, emphasizing the need for comprehensive security testing of all dynamic command generation processes within application frameworks.