CVE-2026-100566 in Line
Summary
by MITRE • 09/26/2026
OpenClaw LINE versions before 2026.8.1 contain an access control vulnerability where group allowlist mode silently inherits DM allowFrom values when groupAllowFrom is not explicitly configured. Attackers with group participation can trigger the agent despite configured group allowlist restrictions when DM access is broader than intended group access.
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Analysis
by VulDB Data Team • 09/26/2026
The identified security flaw in OpenClaw LINE versions prior to 2026.8.1 represents a critical failure in identity and access management logic, specifically within the configuration handling of group-based interaction permissions. This vulnerability stems from an improper inheritance mechanism where the system defaults to using direct message allowlist values when explicit group-level configurations are absent or incomplete. In secure software design, distinct security contexts such as private one-to-one interactions and multi-user group environments should maintain strict isolation in their permission boundaries. However, this implementation flaw causes the application to silently apply broader access controls intended for individual users to the more restrictive group context, thereby undermining the principle of least privilege.
From a technical perspective, the root cause lies in how the configuration parser resolves missing parameters. When an administrator configures a bot or agent with specific restrictions on which groups can interact with it via the groupAllowFrom setting, but fails to explicitly define those values, the system does not default to a deny-all state as expected for security-critical settings. Instead, it falls back to the allowFrom parameter designated for direct messages. This logical error allows any user who is part of an allowed group to bypass intended restrictions if their individual access rights are broader than what was intended for the group context. The vulnerability effectively neutralizes administrative controls designed to limit bot exposure and interaction scope within specific community channels.
The operational impact of this misconfiguration can be severe, particularly in environments where bots handle sensitive data or perform automated actions based on user input. Attackers who have legitimate access to a chat group but are not supposed to trigger the agent due to restrictive allowlist policies can exploit this inheritance behavior to initiate unauthorized interactions. This could lead to information disclosure if the bot reveals internal logic or data, denial of service through resource exhaustion via repeated triggering, or even remote code execution if the input processing pipeline is vulnerable to injection attacks that would otherwise be blocked by proper access controls. The silent nature of the failure means administrators may believe their security policies are enforced when they are not, creating a false sense of security and delaying detection.
This vulnerability aligns with CWE-284 Improper Access Control, specifically reflecting issues related to insufficient authorization checks during configuration resolution. It also maps to MITRE ATT&CK technique T1078 Valid Accounts, as it allows attackers to leverage legitimate group membership credentials to bypass intended access restrictions without needing elevated privileges or exploiting a separate authentication flaw. The lack of explicit defaulting for security-sensitive settings is a common pattern in misconfigured systems that leads to privilege escalation within the application's logical boundaries.
To mitigate this risk, organizations must immediately upgrade OpenClaw LINE installations to version 2026.8.1 or later where these inheritance logic errors have been corrected. Administrators should also conduct an audit of existing bot configurations to ensure that groupAllowFrom parameters are explicitly defined and do not rely on implicit defaults from direct message settings. Implementing a defense-in-depth strategy by validating configuration files against strict security policies during deployment can prevent such misconfigurations in the future. Regular penetration testing focused on access control logic is recommended to identify similar inheritance flaws across other integrated services.