CVE-2026-48207
Apache Fory: PyFory ReduceSerializer Incomplete Policy Enforcement
- State
- Published
- Severity
- 9.8 Critical
- Published
- May 21, 2026
- Updated
- May 21, 2026
- Reserved
- May 21, 2026
Description
Deserialization of untrusted data in Apache Fory PyFory. PyFory's ReduceSerializer could bypass documented DeserializationPolicy validation hooks during reduce-state restoration and global-name resolution. An application is vulnerable if it deserializes attacker-controlled data using PyFory Python-native mode with strict mode disabled and relies on DeserializationPolicy to restrict unsafe classes, functions, or module attributes.
This issue affects Apache Fory: from before 1.0.0.
Mitigation: Users of Apache Fory are recommended to upgrade to version 1.0.0 or later, which enforces DeserializationPolicy validation for the affected ReduceSerializer paths and thus fixes this issue.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 9.8 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | CISA-ADP |
Weaknesses
- CWE-502 Deserialization of Untrusted Data
Affected Products
| Product | Versions |
|---|---|
Apache ForyApache Software Foundation |
|
References
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