PYSEC-2026-2984
Vulnerability from pysec - Published: 2026-07-13 15:19 - Updated: 2026-07-13 16:05Fory 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.
| Name | purl | pyfory | pkg:pypi/pyfory |
|---|
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "pyfory",
"purl": "pkg:pypi/pyfory"
},
"ranges": [
{
"events": [
{
"introduced": "0.13.0"
},
{
"fixed": "1.0.0"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"0.13.0",
"0.13.1",
"0.13.2",
"0.14.0",
"0.14.1",
"0.15.0",
"0.16.0",
"0.17.0"
]
}
],
"aliases": [
"CVE-2026-48207",
"GHSA-m5gw-83w2-7749"
],
"details": "Fory PyFory\u0027s 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.\n\nThis issue affects Apache Fory: from before 1.0.0.\n\nMitigation: 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.",
"id": "PYSEC-2026-2984",
"modified": "2026-07-13T16:05:52.030786Z",
"published": "2026-07-13T15:19:10.366997Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-48207"
},
{
"type": "WEB",
"url": "https://fory.apache.org/security/#cve-2026-48207-pyfory-reduceserializer-deserializationpolicy-bypass"
},
{
"type": "PACKAGE",
"url": "https://github.com/apache/fory"
},
{
"type": "WEB",
"url": "http://www.openwall.com/lists/oss-security/2026/05/21/10"
},
{
"type": "PACKAGE",
"url": "https://pypi.org/project/pyfory"
},
{
"type": "ADVISORY",
"url": "https://github.com/advisories/GHSA-m5gw-83w2-7749"
}
],
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
],
"summary": "Apache Fory PyFory Deserialization of Untrusted Data "
}
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| Author | Source | Type | Date | Other |
|---|
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