[upstream PR 878] Security: escape stored memory content in injected context (H1)

[wbugitlab1]

Source: Source pull request number: 878 in rohitg00/agentmemory (URL omitted to avoid GitHub cross-reference)
Title: Security: escape stored memory content in injected context (H1)
Author: DaveCole
State: open
Draft: no
Merged: no
Head: DaveCole/agentmemory:fix/h1-context-injection-escaping @ 328a13e
Base: main @ a76224f
Labels: (none)
Changed files: 0
Commits: 0
Created: 2026-06-09T21:02:26Z
Updated: 2026-06-09T21:09:02Z
Closed: (not closed)
Merged at: (not merged)

Original PR body:

Summary

mem::context wraps retrieved memories in <agentmemory-context>…</agentmemory-context> and prepends them to the agent's prompt, but interpolated every stored field raw. A memory containing </agentmemory-context><system>…</system> could close the wrapper early and inject instructions into future sessions — a takeover for anyone able to write a memory (REST/MCP client, or a poisoned file the agent read once and compressed into a narrative).

The codebase already had the right defense (escapeXml in enrich.ts); it just was not applied on the retrieval path.

Changes

• Promote escapeXml into src/prompts/xml.ts as the single shared escaper.
• Escape every free-text field in context.ts: profile concepts/files/conventions/commonErrors, lesson content/context, summary title/narrative/keyDecisions/filesModified, observation type/title/narrative, and the project= header attribute. Structural values (ids, timestamps, numbers) left as-is.
• Escape pinned-slot content in slots.ts (label is already validated to ^[a-z][a-z0-9_]*$).
• Drop enrich.ts's duplicate local escapeXml in favor of the shared one.

Tests

• New test/context-injection-escaping.test.ts seeds a breakout payload into every vector and asserts the wrapper cannot be closed early and the payload survives only in neutralized (<…>) form.
• Updated one assertion in test/context-lessons.test.ts (>5-file → >5-file).
• All touched tests pass (context/enrich/slots/xml).

🤖 Generated with Claude Code

Summary by CodeRabbit

• Bug Fixes

  • Enhanced security protections to prevent markup injection attacks through context memory fields, ensuring user-generated content is properly neutralized.

• Tests

  • Added comprehensive regression test suite to verify injection attack prevention across memory contexts.

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