medium6.5
CVE-2026-115918
vLLM: Responses API bypasses trust_request_chat_template for chat_template_kwargs
Impact
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.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| pip | vllm | >= 0.16.0, < 0.32.0 | 0.32.0 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Vllm | Vllm | from 0.16.0 before 0.32.0 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-x567-49g5-p4cf
- https://github.com/vllm-project/vllm/security/advisories/GHSA-x567-49g5-p4cf
- https://nvd.nist.gov/vuln/detail/CVE-2026-115918
- https://github.com/vllm-project/vllm/pull/50300
- https://github.com/vllm-project/vllm/commit/cff08b461e086523cee8bba5bd3c66d302625134
- https://github.com/vllm-project/vllm/releases/tag/v0.32.0