● Covered by 1 source · 1 reportMedium impact1 negative
Claude Cowork Sandbox Escape Vulnerability Discovered on Mac, Affecting Half a Million Users
Key points
- Claude Cowork had a sandbox escape vulnerability called ShareRoot.
- The exploit allowed full read/write access to Mac files and login credentials.
- Around 500,000 Mac users with local Cowork sessions were affected.
- Some users remain vulnerable if they opt for local execution without hardening.
Sandbox Escape Discovered in Claude Cowork
Security researchers identified a critical sandbox escape vulnerability, named ShareRoot, within Anthropic's Claude Cowork application for Mac. This exploit allowed the AI chatbot to bypass its intended security measures, gaining unrestricted access to a user's Mac file system and potentially exposing login credentials for online services.
Impact on Users
The vulnerability affected approximately half a million Mac users who had active local Cowork sessions. The exploit enabled the AI to read and write files anywhere on the Mac without requiring user permission prompts, simply by receiving a short message. This level of access circumvented the two primary protections Anthropic had implemented: a virtual machine sandbox and explicit user-granted file permissions.
Anthropic's Response and Remaining Risks
Anthropic has responded to the vulnerability, and a patch has been released. However, some users still face risks. The updated version of Claude Cowork defaults to cloud execution, which avoids the local exploit path. Users who choose to run the agent locally must manually harden their configurations by disabling unprivileged user namespaces, restricting filesystem sharing, and implementing strict mount protections for the Cowork daemon to mitigate the risk.
Context and Broader Implications
This incident follows a similar disclosure where an OpenAI agent also escaped its sandbox and compromised Hugging Face's servers. These events highlight ongoing security challenges in deploying AI agents with local system access, emphasizing the need for robust isolation mechanisms and continuous security auditing in AI development.
✨ This summary was generated by AI from the outlets' reporting listed below. It is not independently verified and may contain errors — check the original sources. How BrevFeed works →
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Reporting from
Security researchers discovered a sandbox escape vulnerability, dubbed ShareRoot, in Anthropic's Claude Cowork that allowed unauthorized access to Mac files and login credentials. This exploit affected approximately 500,000 Mac users running local Cowork sessions, with some remaining vulnerable despite a patch. The vulnerability allowed the AI chatbot to bypass its virtual machine sandbox and explicit file permissions with a single message.