vllm p2p never connected zmq_exhaustion

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

8.7 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X · score source

EPSS

• CVE-2026-94624: 0.43% estimated exploitation activity in the next 30 days; percentile 37.70 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary When the `OffloadingConnector` uses `TieringOffloadingSpec` with a P2P secondary tier, an API client can submit many unique non-listening peer addresses through `kv_transfer_params.prefill`. vLLM keeps every never-established P2P session and its ZeroMQ sockets after the request finishes. On vLLM 0.26.0, 340 such peers filled the default ZeroMQ context socket quota; creating the next peer raised an uncaught `ZMQError`, terminated `EngineCore`, and shut down the API server. The path was reproduced with a normal API key and no access to the internal P2P listener.

Details

Root cause In vLLM 0.26.0, `P2PSecondaryTierManager.on_new_request()` reads the following request-controlled fields: ```json { "kv_transfer_params": { "prefill": { "kv_request_id": "id", "remote_host": "127.0.0.1", "remote_port": 49101 } } } ``` `on_new_request()` calls `_get_or_create_session(peer_id)`. This calls `ZmqTransport.connect()`, creates a `P2PSession`, and stores it in `_sessions` before…

Published by the source

27 Oct 2026, 14:45 UTC

Last modified by the source

27 Oct 2026, 15:10 UTC

Source last checked

28 Oct 2026, 06:10 UTC

1. Revision 3 · amended · 28 Oct 2026

   Amended from osv record PYSEC-2026-4006

2. Revision 2 · amended · 28 Oct 2026

   Amended from osv record GHSA-frvg-qw88-hww9

3. Revision 1 · created · 27 Oct 2026

   Published from ghsa record GHSA-frvg-qw88-hww9

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# Patch Next advisory brief: CVE-2026-94624

Advisory: vllm p2p never connected zmq_exhaustion
IDs: CVE-2026-94624, GHSA-frvg-qw88-hww9
Record: https://patchnext.com/advisories/cve-2026-94624 (revision 3, source checked 28 Oct 2026, 06:10 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 8.7)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: vllm 0.32.0. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI vllm: affected < 0.32.0; fixed in 0.32.0

## Suggested inspection (read-only)
- `python -m pip show vllm`: prints the installed version. Run with the environment that serves production active.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on vllm.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-frvg-qw88-hww9 (OSV record GHSA-frvg-qw88-hww9 lists affected ranges: PyPI vllm >=0 <0.32.0 (fixed))
- Verified: https://osv.dev/vulnerability/PYSEC-2026-4006 (OSV record PYSEC-2026-4006 lists affected ranges: PyPI vllm >=0 <0.30.0 (fixed))
- Verified: https://github.com/advisories/GHSA-frvg-qw88-hww9 (GitHub-reviewed advisory GHSA-frvg-qw88-hww9 lists affected ranges: PyPI vllm >=0 <0.32.0)

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