🛡️ Sentinel: [HIGH] Fix terminal injection via incomplete OSC terminator

[hongymagic]

🚨 Severity: HIGH
💡 Vulnerability: The regular expression in src/ansi.ts used to strip ANSI escape codes only accounted for the Bell character (\u0007) as an Operating System Command (OSC) sequence terminator. It did not support the String Terminator (ST) sequence \u001B\.
🎯 Impact: A malicious model or prompt injection payload could inject an OSC escape sequence terminated by \u001B\ to bypass the ANSI stripper, potentially leading to terminal injection.
🔧 Fix: Updated ANSI_REGEX to match either \u0007 or \u001B\ as the sequence terminator by modifying \u0007 to (?:\\u0007|\\u001B\\\\).
✅ Verification: Ran unit tests (specifically tests/ansi_security.test.ts), lint checks, and the full test suite via bun run test to verify the fix works and does not introduce regressions.

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PR created automatically by Jules for task 12715310405102718263 started by @hongymagic

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[Copilot]

Pull request overview

This PR patches a terminal injection vulnerability in src/ansi.ts by extending ANSI_REGEX to recognize the String Terminator (\u001B\) as an OSC sequence terminator, in addition to BEL (\u0007). Previously, OSC sequences terminated by ST would bypass the ANSI stripper.

Changes:

• Update ANSI_REGEX in src/ansi.ts to match either \u0007 or \u001B\ as the OSC terminator.
• Add a corresponding entry to .jules/sentinel.md documenting the vulnerability and prevention.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/ansi.ts	Extends the OSC terminator alternation to include ESC \ (ST) alongside BEL.
.jules/sentinel.md	Documents the vulnerability, learning, and prevention for the regex fix.