vLLM is an inference and serving engine for large language models. From 0.16.0 until 0.32.0, the /v1/responses endpoint allows an authenticated caller to place an attacker-controlled template in chat_template_kwargs[chat_template] when no server template is configured. ChatParams.get_apply_chat_template_kwargs() preserves that value without enforcing trust_request_chat_template, so the request can bypass the intended trust policy and cause CPU or memory exhaustion through Jinja rendering. This issue is fixed in version 0.32.0.

Project Subscriptions

Vendors Products
Vllm-project Subscribe
Advisories
Source ID Title
Github GHSA Github GHSA GHSA-x567-49g5-p4cf vLLM: Responses API bypasses trust_request_chat_template for chat_template_kwargs
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Wed, 28 Oct 2026 15:45:00 +0000

Type Values Removed Values Added
CPEs cpe:2.3:a:vllm:vllm:*:*:*:*:*:*:*:*

Tue, 27 Oct 2026 12:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-94
References
Metrics threat_severity

None

threat_severity

Moderate


Mon, 26 Oct 2026 19:15:00 +0000

Type Values Removed Values Added
First Time appeared Vllm
Vllm vllm
Vllm-project
Vllm-project vllm
Vendors & Products Vllm
Vllm vllm
Vllm-project
Vllm-project vllm

Mon, 26 Oct 2026 17:45:00 +0000

Type Values Removed Values Added
Description vLLM is an inference and serving engine for large language models. From 0.16.0 until 0.32.0, the /v1/responses endpoint allows an authenticated caller to place an attacker-controlled template in chat_template_kwargs[chat_template] when no server template is configured. ChatParams.get_apply_chat_template_kwargs() preserves that value without enforcing trust_request_chat_template, so the request can bypass the intended trust policy and cause CPU or memory exhaustion through Jinja rendering. This issue is fixed in version 0.32.0.
Title vLLM: Responses API bypasses trust_request_chat_template for chat_template_kwargs
Weaknesses CWE-400
CWE-770
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}


Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-10-26T17:21:49.719Z

Reserved: 2026-10-23T20:21:45.107Z

Link: CVE-2026-115918

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Analyzed

Published: 2026-10-26T18:17:39.440

Modified: 2026-10-28T15:35:06.973

Link: CVE-2026-115918

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-10-26T17:21:49Z

Links: CVE-2026-115918 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-10-27T13:30:04Z

Weaknesses