Is CVE-2026-25048 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-25048 being exploited in the wild.

How severe is CVE-2026-25048?

High severity, with a CVSS score of 7.5, published 5 March 2026.

Which products and versions are affected?

xgrammar (PyPI) ECOSYSTEM:introduced=0,fixed=0.1.32; Red Hat AI Inference Server 3.2.2.

Is there a fix for CVE-2026-25048?

Yes. xgrammar (PyPI): upgrade to 0.1.32 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-25048 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-25048?

Check whether you run xgrammar (PyPI) or Red Hat AI Inference Server at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-25048: mlc-ai xgrammar uncontrolled recursion in nested syntax

CVE-2026-25048 · Severity: high · CVSS 7.5 · Published 2026-03-05

xgrammar is an open-source library used to ensure that AI models generate structured data, such as JSON or specific code formats. A vulnerability in how the library handles complex, nested instructions can cause the system to crash. This could allow an attacker to disrupt AI services, leading to a denial-of-service (DoS) condition where the AI becomes unavailable to legitimate users.

Technologies: xgrammar (PyPI), Red Hat AI Inference Server. Vendors: PyPI, Red Hat.

Quick answers

Is CVE-2026-25048 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-25048 being exploited in the wild.
How severe is CVE-2026-25048?: High severity, with a CVSS score of 7.5, published 5 March 2026.
Which products and versions are affected?: xgrammar (PyPI) ECOSYSTEM:introduced=0,fixed=0.1.32; Red Hat AI Inference Server 3.2.2.
Is there a fix for CVE-2026-25048?: Yes. xgrammar (PyPI): upgrade to 0.1.32 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-25048 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-25048?: Check whether you run xgrammar (PyPI) or Red Hat AI Inference Server at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

xgrammar (PyPI): upgrade to 0.1.32 or later
```
pip install "xgrammar>=0.1.32"
```

Technical details

A vulnerability exists in xgrammar prior to version 0.1.32 due to uncontrolled recursion (CWE-674) when parsing multi-level nested syntax. An attacker can exploit this by providing a malicious grammar rule containing deeply nested structures (e.g., 30,000 layers of parentheses), which triggers a stack overflow or memory exhaustion. This results in a segmentation fault and a core dump, leading to a denial-of-service (DoS) of the application utilizing the library. The issue is reachable over the network if the application allows user-defined or complex grammar inputs. The vulnerability has been patched in version 0.1.32.

Affected products

mlc-ai xgrammar < 0.1.32
Red Hat Red Hat AI Inference Server 3.2.2
Red Hat Red Hat OpenShift AI 2.25.7

Identifiers

CVE-2026-25048
GHSA-7rgv-gqhr-fxg3
PYSEC-2026-2322

Timeline

2026-03-04: patched: Version 0.1.32 released
2026-03-05: advisory: GitHub Security Advisory published
2026-03-05: disclosed: CVE-2026-25048 published
2026-03-25: patched: Red Hat AI Inference Server 3.2.2 released

References

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