PT-2025-36398 · Xgrammar · Xgrammar

Xendo · CVE-2025-58446 · Published 2025-09-05 · Updated 2026-07-07

Positive Technologies (AI Summary)

CVSS v3.1

7.5

High

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions xgrammar versions 0.1.23

Description xgrammar is an open-source library for efficient, flexible, and portable structured generation. A grammar optimizer introduced in version 0.1.23 can be exploited to cause a denial-of-service (DOS) attack on model providers by processing large grammars at a very low rate.

Recommendations Update to version 0.1.24.

Exploit

Fix

DoS

Allocation of Resources Without Limits

Weakness Enumeration

CWE-770

Related Identifiers

CVE-2025-58446

GHSA-9Q5R-WFVF-RR7F

PYSEC-2026-2055

Affected Products

Xgrammar

References · 12

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/58xxx/CVE-2025-58446.json · Exploit
• https://github.com/mlc-ai/xgrammar/security/advisories/GHSA-9q5r-wfvf-rr7f · Vendor Advisory
• https://github.com/mlc-ai/xgrammar/commit/ced69c3ad2f8f61b516cc278a342e7c644383e27 · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2025-58446 · Security Note
• https://osv.dev/vulnerability/PYSEC-2026-2055 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2025-58446 · Vendor Advisory
• https://osv.dev/vulnerability/GHSA-9q5r-wfvf-rr7f · Vendor Advisory
• https://github.com/mlc-ai/xgrammar · Note
• https://pypi.org/project/xgrammar · Note
• https://github.com/advisories/GHSA-9q5r-wfvf-rr7f · Note
• https://twitter.com/CVEnew/status/1964409189469495318 · Twitter Post
• https://t.me/CVEtracker/31900 · Telegram Post