Auth bypass in Lmcache
CVE-2026-105192
LMCache multiprocess mode, also called distributed mode, opens an unauthenticated ZeroMQ ROUTER so worker processes can register and share KV cache blocks. Messages on that socket are msgpack. Extension code 1 is passed to DeviceIPCWrapper.Deserialize, which calls pickle.loads, while the server is still decoding request arguments and before the handler runs. A single unauthenticated ZMQ DEALER message to the transport port (default 5555) therefore executes code as the user the LMCache process runs as. Official container images run that process as root. The transport binds to localhost unless the operator sets a routable address with --host, which is how multi-node deployments let peers connect.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/LMCache/LMCache (product)
- pypi.org/project/lmcache/ (product)
- github.com/LMCache/LMCache/blob/v0.5.5/lmcache/v1/platform/base/ipc_wrapper.py (technical-description)
- github.com/LMCache/LMCache/blob/v0.3.9/lmcache/v1/multiprocess/custom_types.py (technical-description)
Frequently asked questions
- What is CVE-2026-105192?
- CVE-2026-105192 is a critical-severity vulnerability in Lmcache, classified under Missing Authentication for Critical Function. CVSS score: 9.8/10. Published 2026-10-07.
- How severe is CVE-2026-105192?
- Critical severity. CVSS v3 base score is 9.8 out of 10.