CVE-2026-48207 json
Apache Fory: PyFory ReduceSerializer Incomplete Policy Enforcement
published 5mo ago modified 3mo ago also EUVD-2026-31292 , GHSA-m5gw-83w2-7749 , PYSEC-2026-2984
- 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
Is CVE-2026-48207 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
- Assessed
- 5mo ago
Exploit prediction
0.57% chance of exploitation in the next 30 days, higher than 47% of all scored CVEs (FIRST EPSS, 2026-11-11).
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 |
| GitHub | 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 |
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
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.