GHSA-r3g7-r4hr-m258

### Summary `create_entity`, `link_entities`, `rename_entity`, `unlink_entities` and `delete_entity` regenerate a memory note's body from SQLite at the computed `memory/<type>/<name>.md` path. When a note already existed at that path and was not owned by the entity being written (a hand-authored note, or an orphan left by a different entity whose name sanitized to the same path), its entire body was overwritten on the next write naming that `(type, name)`, keeping only its frontmatter. Separately, several of these tools inserted or removed their SQLite row before the fallible filesystem step, so a refused note write could leave a relation gone, a retired status committed, or the wrong entity deleted. ### Details - `create_entity` and `link_entities` inserted the SQL row or relation before materialization. - `rename_entity` seeded the destination path with a direct atomic write that bypassed the ownership check, and for a status-only rename could commit a retired status with the note write refused. - `unlink_entities` removed the relation row before discovering the source note's rematerialization would be refused. - `delete_entity`'s cascade could delete the target and its relations before a neighbour's note was found to be foreign. The overwrite exists in every released version since `materializeEntity` shipped (`git show v1.0.1:packages/server/src/memory/materialize.ts`). ### Impact An authorized caller with memory-write scope (any agent using the M5 memory tools) can, without intending to, destroy the body of a vault note outside the entity it is writing, and can leave the memory graph inconsistent with the notes on disk. Snapshots-before-write (`restore_note`) mitigate the overwrite only where snapshots are enabled and the note had been written through obsidian-tc before. ### Patches Fixed in 1.31.4 at the shared primitive: `materializeEntity` refuses to write over a note whose `obsidian_tc_id` is missing or belongs to another entity; a new `assertNoteOwnership` pre-check runs before any SQLite mutation in the three lifecycle tools, so a refusal is a no-op; `create_entity` and `link_entities` roll back the row they had inserted. Verified by `test/m5-memory-ownership.test.ts`, which covers all five call sites and the rollback. ### Workarounds None that preserve the tools. Disabling the `write:memory` scope for callers prevents the write path entirely. ### Credit Found by the maintainer while building `obsidian-tc memory import` (PR #978); the vulnerability class was independently confirmed by a cross-vendor adversarial review. ### References - PR #978 (fix and test), CHANGELOG `## [1.31.4] ### Security` - `packages/server/src/memory/materialize.ts`, `packages/server/src/tools/m5/memory-lifecycle-tools.ts` ---