Horizon Alert
Summary of the vulnerability and why it matters
This critical vulnerability in Obsidian-TC, a server for managing Obsidian vault contexts, allows authenticated users to access or modify any vault's data. The issue stems from a failure to properly verify user permissions, potentially exposing sensitive information or allowing unauthorized changes across different vaults. The main concern is confirming relevance and exposure.
- Unchecked user input allowed vault data access.
- Critical flaw permits unauthorized vault data modification.
- Verify if your Obsidian-TC instances are affected.
Attack Path
How an attacker could exploit the issue
An attacker with a valid token could potentially access another user's Obsidian vault and perform unauthorized actions. This is possible because the system does not properly verify if the token used to access a vault actually belongs to that vault, and access controls for folders are globally shared. If successful, an attacker could read, write, or delete sensitive information within the vault.
- Requires a valid token.
- Triggered by unauthorized vault access.
- Risk of data compromise and manipulation.
Live Threat
Current exploitation, exposure, and threat context
When supported by the advisory, an attacker with a valid token could access any configured vault, potentially reading, writing, or deleting its contents. This is possible because the server does not verify that the token's intended vault matches the vault specified in the user's input.
- Vault data could be accessed.
- Any valid token could be misused.
- Data could be altered or deleted.
Operational Fix
Recommended remediation, mitigation, and detection steps
The Obsidian-TC Model Context Protocol server is likely managed by application owners or platform teams responsible for the Obsidian vault environment. The immediate priority is to inventory all instances, confirm their exposure and criticality, and identify the specific owner for each instance before planning remediation.
- Own: Application or Platform Team
- Verify: Reachable instances and vault criticality
- Action: Plan remediation based on confirmed risk
