A critical local code execution vulnerability in Helm allows attackers to overwrite system files and execute arbitrary code by manipulating Chart.yaml and Chart.lock files.

This vulnerability involves improper control of code generation (CWE-94) where Helm fails to stop execution when a Chart.lock file is symlinked to sensitive system files. An attacker can craft a malicious Chart.yaml file that, when dependencies are updated, writes content to a symlinked file, potentially leading to local code execution.

The vulnerability carries a CVSS score of 8.5, indicating a high risk to system integrity and availability. Successful exploitation allows an attacker with local access to overwrite critical system configuration files, which can facilitate privilege escalation, unauthorized system modification, or total system compromise.

Immediate Action: Update Helm to version 3.18.4 or 3.17.4 immediately to include the necessary security checks that prevent symlink-based file overwriting.

Proactive Monitoring: Review audit logs for unexpected file modification activities or unusual command executions initiated by the helm process.

Compensating Controls: Ensure that Helm is executed in isolated environments with minimal filesystem permissions, adhering to the principle of least privilege to restrict the impact of unauthorized file writes.

Public Exploit Available: Yes, a public proof-of-concept exists via the DVKunion/CVE-2025-53547-POC GitHub repository.

The severity of this flaw necessitates immediate attention, particularly for automated build environments where Helm charts are processed frequently. Organizations should prioritize patching all instances of Helm to the specified fixed versions to eliminate the risk of symlink-based code injection. Failing to remediate this vulnerability leaves build systems susceptible to persistent compromise.