Not a U.S. government website. NDD is an independent vulnerability database by Volerion and is not affiliated with or endorsed by NIST or NVD.

CVE-2026-73556 Details

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.

Metrics

CVSS 3.x Severity and Vector Strings:

CNA: [email protected]CVSS-B:5.3 MEDIUMVector:CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

References to Advisories, Solutions, and Tools

By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.

URL	Source(s)	Tag(s)
https://github.com/vllm-project/vllm/security/advisories/GHSA-48jh-3gj7-fg8v	CISA-ADP
https://github.com/vllm-project/vllm/commit/c9a788eedc412acceaa5112e0d44624b49841577	[email protected]
https://github.com/vllm-project/vllm/pull/47595	[email protected]
https://github.com/vllm-project/vllm/releases/tag/v0.26.0	[email protected]
https://github.com/vllm-project/vllm/security/advisories/GHSA-48jh-3gj7-fg8v	[email protected]

Weakness Enumeration

CWE-ID	CWE Name	Source
CWE-1333	Inefficient Regular Expression Complexity	[email protected]
CWE-400	Uncontrolled Resource Consumption	[email protected]

Affected Products

No affected product data is available for this CVE.

Change History

2 change records found show changes

Date	Action	Recorded By
Aug 14, 2026	CVE Modified	CISA-ADP
Aug 13, 2026	New CVE Received	[email protected]