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TI-2025-35692 Aliases CVE-2025-57809GHSA-5cmr-4px5-23pc

XGrammar affected by Denial of Service by infinite recursion grammars

Priority LOW 34CWE-674Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 1 fixed, 1 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA, GitHub and Red Hat. Impact type from CWE-674.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00485 41st percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Partial xgrammar (mlc-ai): 0.1.21xgrammar (PyPI): 0.1.21Red Hat: 10 advisoriesRed Hat: 1 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
mlc-aixgrammarbefore 0.1.210.1.21Patch availableCNA
—xgrammar (PyPI)before 0.1.210.1.21Patch availableGHSA-5cmr-4px5-23pc
  • xgrammar Vendormlc-ai Affected before 0.1.21 Fixed in 0.1.21 Patch available CNA
  • xgrammar (PyPI) Vendor— Affected before 0.1.21 Fixed in 0.1.21 Patch available GHSA-5cmr-4px5-23pc

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:mlc-ai:xgrammar:*:*:*:*:*:*:*:*before 0.1.21Vulnerablemlc-ai
  • cpe:2.3:a:mlc-ai:xgrammar:*:*:*:*:*:*:*:* Versions before 0.1.21 Vulnerable ·mlc-ai

Remediation

  • Fix · CNA xgrammar (mlc-ai) Fixed in 0.1.21
  • Fix · GHSA-5cmr-4px5-23pc xgrammar (PyPI) Fixed in 0.1.21 Advisory →

Red Hat 10 advisories

  • RHSA-2025:19430 Released 2025-11-03 · Red Hat rating Important
    Red Hat Enterprise Linux AI 1.5 (NVIDIA)
    • Red Hat Enterprise Linux AI 1.5 registry.redhat.io/rhelai1/bootc-azure-nvidia-rhel9
  • RHSA-2025:19429 Released 2025-11-03 · Red Hat rating Important
    Red Hat Enterprise Linux AI 1.5 (NVIDIA)
    • Red Hat Enterprise Linux AI 1.5 registry.redhat.io/rhelai1/bootc-aws-nvidia-rhel9
  • RHSA-2025:19428 Released 2025-11-03 · Red Hat rating Important
    Red Hat Enterprise Linux AI 1.5 (NVIDIA)
    • Red Hat Enterprise Linux AI 1.5 registry.redhat.io/rhelai1/bootc-nvidia-rhel9
Show 7 more Red Hat advisories
  • RHSA-2025:19427 Released 2025-11-03 · Red Hat rating Important
    Red Hat Enterprise Linux AI 1.5 (AMD)
    • Red Hat Enterprise Linux AI 1.5 registry.redhat.io/rhelai1/bootc-amd-rhel9
  • RHSA-2025:19426 Released 2025-11-03 · Red Hat rating Important
    Red Hat Enterprise Linux AI 1.5 (NVIDIA)
    • Red Hat Enterprise Linux AI 1.5 registry.redhat.io/rhelai1/bootc-gcp-nvidia-rhel9
  • RHSA-2025:19425 Released 2025-11-03 · Red Hat rating Important
    Red Hat Enterprise Linux AI 1.5 (AMD)
    • Red Hat Enterprise Linux AI 1.5 registry.redhat.io/rhelai1/instructlab-amd-rhel9
  • RHSA-2025:19424 Released 2025-11-03 · Red Hat rating Important
    Red Hat Enterprise Linux AI 1.5 (AMD)
    • Red Hat Enterprise Linux AI 1.5 registry.redhat.io/rhelai1/bootc-azure-amd-rhel9
  • RHSA-2025:19423 Released 2025-11-03 · Red Hat rating Important
    Red Hat Enterprise Linux AI 1.5 (NVIDIA)
    • Red Hat Enterprise Linux AI 1.5 registry.redhat.io/rhelai1/instructlab-nvidia-rhel9
  • RHSA-2025:19422 Released 2025-11-03 · Red Hat rating Important
    Red Hat Enterprise Linux AI 1.5 (Intel Gaudi)
    • Red Hat Enterprise Linux AI 1.5 registry.redhat.io/rhelai1/bootc-intel-rhel9
  • RHSA-2025:19421 Released 2025-11-03 · Red Hat rating Important
    Red Hat Enterprise Linux AI 1.5 (Intel Gaudi)
    • Red Hat Enterprise Linux AI 1.5 registry.redhat.io/rhelai1/instructlab-intel-rhel9

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat AI Inference ServerAffectedNo fix yet
Red Hat Enterprise Linux AI 1.5Fixed RHSA-2025:19421, RHSA-2025:19422, RHSA-2025:19423, RHSA-2025:19424, RHSA-2025:19425, RHSA-2025:19426, RHSA-2025:19427, RHSA-2025:19428, RHSA-2025:19429, RHSA-2025:19430

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-57809
  2. 2026-10-03 Alias added: GHSA-5cmr-4px5-23pc

References

Exploit 1

Patch 1

Advisory 2

Other 1

  • TI-2025-36204 xgrammar vulnerable to denial of service by huge enum grammar CVSS 4.0MEDIUM 6.9
  • TI-2026-20232 xgrammar: Multi-layer nesting causes DoS CVSS 4.0HIGH 8.7
  • TI-2025-23460 Denial of Service by abusing xgrammar unbounded cache in memory CVSS 3.1MEDIUM 6.5

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences