# CVE-2026-105192: LMCache Unauthenticated RCE in multiprocess mode via pickle deserialization

> Unauthenticated attackers can execute arbitrary code via pickle deserialization in LMCache multiprocess mode if the transport port is exposed.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 7 Oct 2026
- **Updated:** 29 Oct 2026
- **Also known as:** GHSA-w5f2-9q9c-ff4h

## What is CVE-2026-105192?

CVE-2026-105192 is a critical unsafe deserialization vulnerability in LMCache, published on 7 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

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. The decode path shipped in v0.3.9 and is present through v0.5.5, including the v0.5.6 release candidates. v0.5.6, published on 2026-10-14, removes pickle.loads from this path.

Weakness: CWE-502 (Deserialization of Untrusted Data), CWE-306 (Missing Authentication for Critical Functionality)

## Which versions are affected by CVE-2026-105192?

2 open source packages ship an affected version, including lmcache.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `lmcache` | PyPI | From 0.3.9 | 0.5.6 |
| `lmcache` | PyPI | From 0.3.9 | 0.5.6 |

## How do I fix CVE-2026-105192?

Upgrade lmcache to 0.5.6 or later.

## Is CVE-2026-105192 being exploited?

There is no known exploitation of CVE-2026-105192 in the wild and no public exploit code.

Public exploit code:

- CVE-2026-105192 is a critical (CVSS 9.8) vulnerability in LMCache, an open-source distributed key-value cache for LLM inference engines like vLLM. (github_poc): https://github.com/rxsklife/CVE-2026-105192

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-105192 and fix it if it is affected.

What it is: CVE-2026-105192 is a critical unsafe deserialization vulnerability in LMCache, published on 7 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-105192 in the wild and no public exploit code.

Affected packages and fixed versions:
- lmcache (PyPI): affected from 0.3.9; fixed in 0.5.6
- lmcache (PyPI): affected from 0.3.9; fixed in 0.5.6

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-105192/ (Markdown: https://insights.sbomify.com/CVE-2026-105192/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-105192
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-105192
- OSV: https://osv.dev/vulnerability/CVE-2026-105192

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-105192/
Summaries are generated and may contain mistakes; the official description above is the record.