Resource exhaustion in Mlc-ai Xgrammar

CVE-2025-58446

xgrammar is an open-source library for efficient, flexible, and portable structured generation. A grammar optimizer introduced in 0.1.23 processes large grammars (>100k characters) at very low rates, and can be used for DOS of model provid…

EPSS: 0.005 (38.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-58446?
CVE-2025-58446 is a high-severity vulnerability in Mlc-ai Xgrammar, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 7.5/10. Published 2025-09-06.
How severe is CVE-2025-58446?
High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2025-58446 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.