CVE-2026-48207 json
Apache Fory: PyFory ReduceSerializer Incomplete Policy Enforcement
published 2026-05-21 5 mo ago modified 2026-07-23 3 mo ago also GHSA-m5gw-83w2-7749 , PYSEC-2026-2984 , EUVD-2026-31292
- cvss
- 9.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 47%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- pypi pyfory 1.0.0
- Apache Software Foundation Apache Fory 1.0.0
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
- Assessed
- 5 mo ago
Exploit prediction
0.57% chance of exploitation in the next 30 days, higher than 47% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CISA ADP | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| CNA | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| OSV | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| GitHub | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| pypi | pyfory | >=0.13.0, <1.0.0 |
1.0.0 |
Affected products
- Apache Software Foundation Apache Fory
Classification
- Weakness
-
- CWE-502 Deserialization of Untrusted Data
References
-
fory.apache.org
/security/#cve-2026-48207-pyfory-reduceserializer-deserializationpolicy-bypass
vendor-advisory, web
-
openwall.com
/lists/oss-security/2026/05/21/10
web, mailing-list, third-party-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2026-48207
advisory
-
github.com
/apache/fory
package
-
pypi.org
/project/pyfory
package
-
github.com
/advisories/GHSA-m5gw-83w2-7749
advisory
Sources
- CVE List CVE-2026-48207
- GitHub Advisory GHSA-m5gw-83w2-7749
- NVD CVE-2026-48207
- OSV PYSEC-2026-2984
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