| Component | vLLM |
| Severity | medium (CVSS 4.3) |
| CVSS vector | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L |
| Published (NVD) | 2026-09-15 |
| Affected versions | <= 0.27.1 read from the advisory text: NVD has not published CPE data yet |
| Fixed in | see the vendor advisory |
| Weakness | CWE-400CWE-404 |
| CISA KEV | not listed |
NVD description
A vulnerability was determined in vllm-project vLLM up to 0.27.1. This affects an unknown part of the file /v1/chat/completions of the component Jinja Template Rendering. This manipulation of the argument chat_template causes resource consumption. The attack can be initiated remotely. The exploit has been publicly disclosed and may be utilized. The pull request to fix this issue awaits acceptance.
What to do
- NVD lists no fixed version yet: follow the vendor advisory below and keep vLLM off the public internet until a fix ships.
- Do not expose the component's API or UI to the internet without authentication in front of it.
Sources
- NVD: CVE-2026-90878
- https://github.com/vllm-project/vllm/
- https://github.com/vllm-project/vllm/issues/52025
- https://github.com/vllm-project/vllm/pull/52163
- https://vuldb.com/cve/CVE-2026-90878
- https://vuldb.com/submit/927901
- https://vuldb.com/vuln/403472
- https://vuldb.com/vuln/403472/cti
Read more
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