Description
vLLM through 0.29.0 contains a resource exhaustion vulnerability in MooncakeConnector where rejected prefill requests create ownerless transfer placeholders that are never reclaimed. Attackers can send rejected requests to exhaust sender task pools, causing valid requests to be delayed by up to 480 seconds while health checks continue returning success.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| vllm-project | vllm | ≤ 0.29.0 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| PyPI | vllm | < 0.30.0 | 0.30.0 | PYSEC-2026-4007 |
Advisories 1
- WID-SEC-2026-3507 vllm: Mehrere Schwachstellen ermöglichen Denial of Service BSI CERT-Bund (WID) · Nov 9, 2026
References
- Pull Request #51236 issue-tracking patch
- https://github.com/vllm-project/vllm/blob/v0.29.0/vllm/distributed/kv_transfer/kv_connector/v1/mooncake/mooncake_connector.py#L1234-L1242 technical-description
- https://github.com/vllm-project/vllm product
- VulnCheck Advisory: vLLM through 0.29.0 Resource Exhaustion via Ownerless Mooncake Transfer Placeholders third-party-advisory