Is CVE-2026-48207 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-48207 being exploited in the wild.

How severe is CVE-2026-48207?

Critical severity, with a CVSS score of 9.8, published 21 May 2026.

Which products and versions are affected?

Apache Software Foundation PyFory >= 0.13.0, < 1.0.0, 0.13.0 through 0.17.0; pyfory (PyPI) ECOSYSTEM:introduced=0.13.0,fixed=1.0.0.

Is there a fix for CVE-2026-48207?

Yes. pyfory (PyPI): upgrade to 1.0.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-48207 attacked?

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

Am I affected by CVE-2026-48207?

Check whether you run Apache Software Foundation PyFory or pyfory (PyPI) 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-2026-48207: Apache Fory PyFory deserialization bypass in ReduceSerializer

Q: Is there a fix for CVE-2026-48207?

Yes. pyfory (PyPI): upgrade to 1.0.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-48207 attacked?

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

Q: Am I affected by CVE-2026-48207?

Check whether you run Apache Software Foundation PyFory or pyfory (PyPI) 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-2026-48207 · Severity: critical · CVSS 9.8 · Published 2026-05-21

Apache Fory (PyFory) is a Python library used for data serialization. A security flaw allows attackers to bypass safety filters when the library processes specially crafted data. If exploited, this could allow an attacker to execute unauthorized commands or take full control of the server running the application.

Vendors: Apache Software Foundation, PyPI.

Quick answers

Is CVE-2026-48207 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-48207 being exploited in the wild.
How severe is CVE-2026-48207?: Critical severity, with a CVSS score of 9.8, published 21 May 2026.
Which products and versions are affected?: Apache Software Foundation PyFory >= 0.13.0, < 1.0.0, 0.13.0 through 0.17.0; pyfory (PyPI) ECOSYSTEM:introduced=0.13.0,fixed=1.0.0.
Is there a fix for CVE-2026-48207?: Yes. pyfory (PyPI): upgrade to 1.0.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-48207 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-48207?: Check whether you run Apache Software Foundation PyFory or pyfory (PyPI) 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

pyfory (PyPI): upgrade to 1.0.0 or later
```
pip install "pyfory>=1.0.0"
```

Technical details

A deserialization vulnerability (CWE-502) exists in Apache Fory's PyFory component within the ReduceSerializer. The component fails to properly enforce DeserializationPolicy validation hooks during reduce-state restoration and global-name resolution when running in Python-native mode with strict mode disabled. An unauthenticated remote attacker can exploit this by providing malicious serialized data that bypasses intended restrictions on unsafe classes or functions. This can lead to arbitrary code execution. The issue is resolved in version 1.0.0 by enforcing validation across all affected serializer paths.

Affected products

Apache Software Foundation PyFory >= 0.13.0, < 1.0.0

Identifiers

CVE-2026-48207
GHSA-m5gw-83w2-7749
PYSEC-2026-2984

Timeline

2026-05-21: disclosed
2026-05-21: advisory
2026-06-30: patched: Advisory updated with patch details

References

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