CVE-2026-28363 in OpenClaw
Summary
by MITRE • 02/27/2026
In OpenClaw before 2026.2.23, tools.exec.safeBins validation for sort could be bypassed via GNU long-option abbreviations (such as --compress-prog) in allowlist mode, leading to approval-free execution paths that were intended to require approval. Only an exact string such as --compress-program was denied.
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Analysis
by VulDB Data Team • 03/11/2026
The vulnerability identified as CVE-2026-28363 affects OpenClaw versions prior to 2026.2.23 and represents a critical authorization bypass flaw in the tools.exec.safeBins validation mechanism. This issue specifically impacts the sort command's validation logic where the system incorrectly accepts GNU long-option abbreviations as valid inputs, allowing attackers to execute commands that should have been restricted. The flaw demonstrates a classic improper input validation vulnerability that can be classified under CWE-20, which encompasses weaknesses related to improper input validation in software systems.
The technical implementation of this vulnerability exploits the lenient parsing behavior of GNU command-line tools where long options can be abbreviated to any unique prefix. In the context of OpenClaw's allowlist validation, when the system processes the --compress-prog argument, it fails to recognize this as a potentially dangerous abbreviation of --compress-program and incorrectly grants execution privileges. This bypass mechanism specifically targets the allowlist mode functionality where only explicitly permitted commands should be executable, creating a security gap that allows arbitrary command execution without proper authorization.
The operational impact of this vulnerability extends beyond simple command execution, as it fundamentally undermines the security model of the tools.exec.safeBins validation system. Attackers can leverage this flaw to execute potentially malicious commands that would normally be blocked by the validation process, creating a pathway for privilege escalation and unauthorized system access. The vulnerability operates at the command-line interface level, making it particularly dangerous in environments where OpenClaw is used for system administration tasks or automated processing of untrusted input data.
Security controls based on input validation and command execution restrictions become ineffective when this vulnerability is exploited, as the system's authorization model fails to properly distinguish between legitimate and malicious command arguments. The flaw demonstrates a critical failure in the principle of least privilege implementation, where the system grants execution rights based on incomplete or inaccurate parameter validation. This issue aligns with ATT&CK technique T1059.001 for command and scripting interpreter and T1068 for exploit for privilege escalation, as it enables unauthorized execution of system commands through improper input handling.
Mitigation strategies should focus on implementing stricter validation of command-line arguments, particularly for long options that may be abbreviated. The recommended approach involves enhancing the validation logic to enforce exact string matching for all command-line parameters, rather than relying on partial matching behavior. Organizations should also consider implementing additional layers of protection such as mandatory access controls, input sanitization, and comprehensive logging of all execution attempts. The fix requires updating the OpenClaw software to version 2026.2.23 or later, where the validation mechanism has been corrected to properly reject abbreviated long options while maintaining legitimate functionality.