Lmcache
Monthly
Weak hash truncation in LMCache up to 0.4.6 allows a local low-privilege attacker to induce KV cache collisions by exploiting the severely constrained 16-bit integer output of `hex_hash_to_int16` in the vLLM integration's KV Cache Handler. The function masks multimodal content hash identifiers to at most 65,536 unique values, making engineered collisions feasible and causing incorrect cached KV entries to be served, affecting both cache integrity and availability. A proof-of-concept has been published on GitHub (issue #3301); no public exploit confirmed in active exploitation and no CISA KEV listing exists.
Weak hash truncation in LMCache up to 0.4.6 allows a local low-privilege attacker to induce KV cache collisions by exploiting the severely constrained 16-bit integer output of `hex_hash_to_int16` in the vLLM integration's KV Cache Handler. The function masks multimodal content hash identifiers to at most 65,536 unique values, making engineered collisions feasible and causing incorrect cached KV entries to be served, affecting both cache integrity and availability. A proof-of-concept has been published on GitHub (issue #3301); no public exploit confirmed in active exploitation and no CISA KEV listing exists.