CVE-2021-23154 in Lens
Summary
by MITRE • 01/10/2022
In Lens prior to 5.3.4, custom helm chart configuration creates helm commands from string concatenation of provided arguments which are then executed in the user's shell. Arguments can be provided which cause arbitrary shell commands to run on the system.
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Analysis
by VulDB Data Team • 01/13/2022
The vulnerability identified as CVE-2021-23154 affects Lens versions prior to 5.3.4 and represents a critical command injection flaw in the custom helm chart configuration functionality. This issue stems from improper input validation and handling within the helm command execution process, where user-provided arguments are concatenated into shell commands through string manipulation rather than proper parameterization. The vulnerability resides in the software's failure to sanitize or escape user inputs before incorporating them into shell execution contexts, creating a pathway for malicious command injection attacks.
The technical implementation of this vulnerability involves the application's use of string concatenation to build helm commands for execution within the user's shell environment. When users configure custom helm charts, they can provide various arguments and parameters that should be safely processed by the application. However, the flawed implementation directly incorporates these user inputs into shell command strings without adequate sanitization or validation, allowing attackers to inject malicious shell commands through specially crafted input values. This approach violates fundamental security principles for shell command execution and creates a direct vector for arbitrary code execution on the affected system.
The operational impact of this vulnerability is severe and far-reaching, as it enables remote code execution capabilities for attackers who can influence the helm chart configuration process. An attacker who can manipulate the custom helm chart parameters or gain access to a system with Lens installed could execute arbitrary commands with the privileges of the user running the Lens application. This could lead to complete system compromise, data exfiltration, privilege escalation, or the installation of persistent backdoors. The vulnerability affects any environment where Lens is used for helm chart management, particularly in development and production environments where users might have access to the configuration interfaces.
Mitigation strategies for CVE-2021-23154 should focus on immediate remediation through upgrading to Lens version 5.3.4 or later, which contains the necessary patches to address the command injection vulnerability. Organizations should also implement strict input validation and sanitization measures for any user-provided parameters that are later used in shell command construction. The fix should employ proper parameterization techniques rather than string concatenation, ensuring that user inputs are treated as literal values rather than executable code. Additionally, implementing principle of least privilege access controls and restricting the ability to configure custom helm charts to trusted users only can significantly reduce the attack surface. This vulnerability aligns with CWE-78 which describes improper neutralization of special elements used in shell commands, and maps to ATT&CK technique T1059.001 for command and scripting interpreter. Organizations should also consider implementing runtime application self-protection measures and monitoring for suspicious command execution patterns as part of their defensive strategies.