Improper Input Validation

xgrammar is vulnerable to improper input validation. The vulnerability is due to the lack of validation on user-supplied grammars, which allows an attacker to easily trigger the flaw and potentially exploit affected tools that pass untrusted grammars to 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 providers. This issue is fixed in version 0.1.24. Mitigation Upgrad...

Allocation of Resources Without Limits or Throttling

Overview xgrammar is an Efficient, Flexible and Portable Structured Generation Affected versions of this package are vulnerable to Allocation of Resources Without Limits or Throttling due to wrong boundary check in the earley parser. An attacker can cause resource exhaustion and disrupt service...

CVE-2025-58446 xgrammar vulnerable to denial of service by huge enum grammar

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 providers. This issue is fixed in version 0.1.24...

CVE-2025-58446 xgrammar vulnerable to denial of service by huge enum grammar

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 providers. This issue is fixed in version 0.1.24...

CVE-2025-58446

The CVE-2025-58446 entry concerns xgrammar, an open-source library for structured generation. The root cause is a grammar optimizer introduced in 0.1.23 that processes very large grammars (>100k characters) with very low throughput, enabling denial-of-service against model providers. A fix is ...

CVE-2025-58446 xgrammar vulnerable to denial of service by huge enum grammar

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 providers. This issue is fixed in version 0.1.24...

XGrammar 安全漏洞

XGrammar is a fast, flexible and portable structured generation tool from mlc-ai open source. A security vulnerability exists in xgrammar version 0.1.23, which stems from the syntax optimizer being inefficient when processing large grammars, and could lead to a denial of service attack...

xgrammar vulnerable to denial of service by huge enum grammar

Summary Provided grammar, would fit in a context window of most of the models, but takes minutes to process in 0.1.23. In testing with 0.1.16 the parser worked fine so this seems to be a regression caused by Earley parser. Details Full reproducer provider in the POC section. The resulting grammar...

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...

Uncontrolled Recursion

Overview xgrammar is an Efficient, Flexible and Portable Structured Generation Affected versions of this package are vulnerable to Uncontrolled Recursion via user supplied grammars involving left recursion. Details Denial of Service DoS describes a family of attacks, all aimed at making a system...

CVE-2025-57809 XGrammar affected by Denial of Service by infinite recursion grammars

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...

CVE-2025-57809

CVE-2025-57809 affects XGrammar. Prior to 0.1.21, there is an infinite recursion issue in the grammar; this is resolved in version 0.1.21. CVSSv3.1 base score 7.5 (HIGH) with availability impact; CVSS4 base score 8.7 (HIGH) with high availability impact. Remediation: upgrade XGrammar to 0.1.21 or...

CVE-2025-57809 XGrammar affected by Denial of Service by infinite recursion grammars

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...

CVE-2025-57809 XGrammar affected by Denial of Service by infinite recursion grammars

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...

XGrammar affected by Denial of Service by infinite recursion grammars

Summary This issue: http://github.com/mlc-ai/xgrammar/issues/250 should have it's own security advisory. Since several tools accept and pass user supplied grammars to xgrammar, and it is so easy to trigger it seems like a High...

GHSA-5CMR-4PX5-23PC XGrammar affected by Denial of Service by infinite recursion grammars

Summary This issue: http://github.com/mlc-ai/xgrammar/issues/250 should have it's own security advisory. Since several tools accept and pass user supplied grammars to xgrammar, and it is so easy to trigger it seems like a High...

PT-2025-34711

Name of the Vulnerable Software and Affected Versions: XGrammar versions prior to 0.1.21 Description: XGrammar, an open-source library for structured generation, contains an infinite recursion issue within its grammar. This issue was addressed in version 0.1.21. Recommendations: Update to version...

XGrammar 安全漏洞

XGrammar is a fast, flexible and portable structured generation tool from mlc-ai open source. A security vulnerability exists in XGrammar versions prior to 0.1.21, which stems from an infinite recursion problem in the syntax...

Uncaught Exception

Overview vllm is an A high-throughput and memory-efficient inference and serving engine for LLMs Affected versions of this package are vulnerable to Uncaught Exception through the guidedregex parameter when using xgrammar validation. An attacker can cause the application to crash by sending an...