Anthropic Sandbox Runtime Incorrectly Implemented Network Sandboxing
CVE-2025-66479

1.8LOW

Key Information:

Vendor

Anthropic-experimental

Status
Sandbox-runtime
Vendor
CVE Published:
4 December 2025

What is CVE-2025-66479?

Anthropic Sandbox Runtime is a lightweight sandboxing tool for enforcing filesystem and network restrictions on arbitrary processes at the OS level, without requiring a container. Prior to 0.0.16, due to a bug in sandboxing logic, sandbox-runtime did not properly enforce a network sandbox if the sandbox policy did not configure any allowed domains. This could allow sandboxed code to make network requests outside of the sandbox. A patch for this was released in v0.0.16.

Affected Version(s)

sandbox-runtime < 0.0.16

References

https://github.com/anthropic-experimental/sandbox-runtime...
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https://github.com/anthropic-experimental/sandbox-runtime...
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CVSS V4

Score:
1.8
Severity:
LOW
Confidentiality:
Low
Integrity:
None
Availability:
None
Attack Vector:
Local
Attack Complexity:
Low
Attack Required:
Physical
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

JSON
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CVE-2025-66479 : Sandboxing Bug in Anthropic Sandbox Runtime Affects Network Security