What changed
The MPBench preprint identifies four memory-write channels, nine memory-system vulnerabilities, and six attack classes, finding that agents which write memory more aggressively can become easier to manipulate.
Why it matters
Persistent memory creates a durable attack surface: one malicious interaction can influence later tasks even after the original content has disappeared.
What to do
Treat memory writes as privileged actions with provenance, confidence, expiry, conflict checks, user visibility, and revocation.
Caveat
Benchmark attacks do not estimate real-world frequency, and defenses against prompt injection may not transfer directly to memory poisoning.