CVE-2025-32381

XGrammar is an open-source library for efficient, flexible, and portable structured generation. Prior to 0.1.18, Xgrammar includes a cache for compiled grammars to increase performance with repeated use of the same grammar. This cache is held in memory. Since the cache is unbounded, a system making use of xgrammar can be abused to fill up a host's memory and case a denial of service. For example, sending many small requests to an LLM inference server with unique JSON schemas would eventually cause this denial of service to occur. This vulnerability is fixed in 0.1.18.

The following products are affected by CVE-2025-32381 vulnerability.

Here, you will find a curated list of external links that provide in-depth information to CVE-2025-32381.

URL	Resource
https://github.com/mlc-ai/xgrammar
https://github.com/mlc-ai/xgrammar/pull/243
https://github.com/mlc-ai/xgrammar/security/advisories/GHSA-389x-67px-mjg3
https://github.com/vllm-project/vllm/pull/16283
https://nvd.nist.gov/vuln/detail/CVE-2025-32381
https://www.cve.org/CVERecord?id=CVE-2025-32381