CTI · reviewed · 2026-10-08

CVE-2026-105192: Unpatched critical RCE in LMCache (CVSS 9.8)

Full story & timeline

MITRE ATT&CK

• T1190 Exploit Public-Facing Application Initial Access

Indicators

Observables tied to this case, from the curated feed. raw sidecar

• cybersecurefox.com domain · active · corroborated

Detections

Detection content derived from this case analysis. Status: experimental — not validated against live telemetry.

Sigma raw

title: LMCache ZeroMQ Unpickle RCE Exposure on TCP 5555
id: 5cbc4d0a-e7ab-4b48-bff0-00c3fbe4e21a
status: experimental
description: >
    Detects network flows to TCP port 5555, the default ZeroMQ
    multiprocess transport of the LMCache KV-cache server used by vLLM.
    CVE-2026-105192 (CVSS 9.8, unpatched as of 2026-10-07) lets an
    unauthenticated peer run arbitrary code via a single ZeroMQ message
    (msgpack extension code 1 triggers pickle.loads before the message
    type is validated), official container images run the server as root,
    and the published Kubernetes daemonset example binds 0.0.0.0:5555 —
    so routable 5555 flows are worth triage while no fix exists.
references:
    - https://thehackernews.com/2026/10/unpatched-critical-lmcache-flaw-lets.html
    - https://beyondmachines.net/event_details/unpatched-critical-rce-vulnerability-in-lmcache-exposes-llm-infrastructure-to-remote-takeover-u-2-9-i-r/gD2P6Ple2L
author: Tia N. List
date: 2026/10/08
tags:
    - attack.t1190
logsource:
    category: network_connection
    product: linux
detection:
    selection:
        DestinationPort: 5555
    filter_local:
        DestinationIp:
            - '127.0.0.1'
            - '::1'
    condition: selection and not filter_local
falsepositives:
    - Other ZeroMQ-based services or unrelated applications that also use TCP 5555
    - Legitimate in-cluster LMCache traffic between vLLM pods, if it egresses with routable addresses
    - Internal management or health-check traffic to port 5555
level: medium

References

• https://thehackernews.com/2026/10/unpatched-critical-lmcache-flaw-lets.html
• https://beyondmachines.net/event_details/unpatched-critical-rce-vulnerability-in-lmcache-exposes-llm-infrastructure-to-remote-takeover-u-2-9-i-r/gD2P6Ple2L