CVEvulnerability
CVE-2026-73556
5.3 MEDIUM
Official page ↗
- Status
- Analyzed
- Published
- 2026-08-13
- Last modified
- 2026-09-28
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 5.3 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
- Weaknesses
- CWE-1333, CWE-400
Description
vLLM is an inference and serving engine for large language models. Prior to 0.26.0, the structured_outputs.regex parameter in vllm/v1/structured_output/backend_lm_format_enforcer.py is passed to lmformatenforcer.RegexParser without compile_regex_with_timeout or validation in validate_structured_output_request_lm_format_enforcer, allowing an unauthenticated /v1/completions request against the lm-format-enforcer backend to consume a CPU core and stall the structured-output engine path with a catastrophic regular expression. This issue is fixed in version 0.26.0.
Affected configurations
• vllm vllm (< 0.26.0)
Related
References
- https://github.com/vllm-project/vllm/commit/c9a788eedc412acceaa5112e0d44624b49841577 Patch
- https://github.com/vllm-project/vllm/pull/47595 Issue Tracking, Patch
- https://github.com/vllm-project/vllm/releases/tag/v0.26.0 Release Notes
- https://github.com/vllm-project/vllm/security/advisories/GHSA-48jh-3gj7-fg8v Vendor Advisory
- https://github.com/vllm-project/vllm/security/advisories/GHSA-48jh-3gj7-fg8v Vendor Advisory