Vulnerability in Mlc-ai Xgrammar

CVE-2025-57809

XGrammar is an open-source library for efficient, flexible, and portable structured generation. Prior to version 0.1.21, XGrammar has an infinite recursion issue in the grammar. This issue has been resolved in version 0.1.21.

EPSS: 0.004 (34.9th 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-2025-57809?
CVE-2025-57809 is a high-severity vulnerability in Mlc-ai Xgrammar, classified under Uncontrolled Recursion. CVSS score: 7.5/10. Published 2025-08-25.
How severe is CVE-2025-57809?
High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2025-57809 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.