Deserialization in Apache Fory
CVE-2026-48207
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.
Vulnerability class: Insecure Deserialization
EPSS: 0.006 (45.2th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Apache Fory
- Apache Software Foundation Fory — versions 0.13.0
Weakness classification (CWE)
References
- security@apache.org (vendor-advisory, Vendor Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2026-48207?
- CVE-2026-48207 is a critical-severity vulnerability in Apache Fory, classified under Deserialization of Untrusted Data. CVSS score: 9.8/10. Published 2026-05-21.
- How severe is CVE-2026-48207?
- Critical severity. CVSS v3 base score is 9.8 out of 10.