CVE-2026-48207
📛 CVE Title
Apache Fory: PyFory ReduceSerializer Incomplete Policy Enforcement
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.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- apache
- CVSS severity
- critical
- CVSS score
- 9.8 / 10
- CVSS vector
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- Effective score
- 9.8 / 10 CRITICAL source: CNA overview
- CWE(s)
-
CWE-502 - Reserved
- 2026-05-21
- Published
- 2026-05-21 15:51 UTC
- Last updated
- 2026-05-21 18:37 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/48xxx/CVE-2026-48207.json
- Linked Threat
- CVE-2026-48207 — CVE-2026-48207
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-05-21 17:16:21 UTC
- NVD last modified
- 2026-05-21 19:16:53 UTC
- NVD CVSS v3.1
- 9.8 / 10 CRITICAL source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
- NVD CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- Exploitability subscore
- 3.9 / 10
- Impact subscore
- 5.9 / 10
- EPSS score
- 0.0004 (probability of exploitation in next 30 days)
- EPSS percentile
- 12.58% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24
NVD / KEV / EPSS data refreshed 2026-05-25 00:27 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-31292 - Assigner
- apache
- Published
- May 21, 2026, 3:51:12 PM
- Updated
- May 21, 2026, 6:37:32 PM
- EUVD base score (CVSS 3.1)
-
9.8 / 10
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EUVD-reported EPSS
- 0.1400
- Vendors
- Apache Software Foundation
- Products
-
Apache Fory (0.13.0 <1.0.0)
- Aliases
-
GHSA-m5gw-83w2-7749
ENISA 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.
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Apache Software Foundation | Apache Fory |
0.13.0 (affected)
|
— |
Vendor references (1)
References embedded in the original CVE record by the assigning CNA.
MITRE references (1) cveawg.mitre.org
Pulled from MITRE's CVE Services API by the 🛰 Backfill from MITRE button.
Web references (4)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- https://www.first.org/epss/ tenable:www.first.org
- http://www.openwall.com/lists/oss-security/2026/05/21/10 tenable:www.openwall.com
- https://nvd.nist.gov/vuln/detail/CVE-2026-48207 tenable:nvd.nist.gov
- https://www.cve.org/CVERecord?id=CVE-2026-48207 tenable:www.cve.org
NVD-tagged references (2)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- http://www.openwall.com/lists/oss-security/2026/05/21/10 af854a3a-2127-422b-91ae-364da2661108
- https://fory.apache.org/security/#cve-2026-48207-pyfory-reduceserializer-deserializationpolicy-bypass security@apache.org
Remediations (19)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:cyberpress.org
The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has added two actively exploited Microsoft Defender vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog, issuing an urgent remediation directive for federal agencies with a due date of June 3, 2026 .
2026-05-24 12:02 UTC -
web:cybersecuritynews.com
Microsoft released its March 2026 Patch Tuesday security update on March 10, 2026 , addressing 78 vulnerabilities across Windows, Microsoft Office, Azure, SQL Server, and .NET. The update includes one actively exploited zero-day vulnerability and multiple Critical-rated flaws demanding immediate attention from security teams. The most urgent fix this month is CVE - 2026 -21262, the sole zero-day ...
2026-05-24 12:02 UTC -
web:nvd.nist.gov
An official website of the United States government Here's how you know
2026-05-24 12:02 UTC -
web:portal.msrc.microsoft.com
The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.
2026-05-24 12:02 UTC -
web:www.bleepingcomputer.com
Microsoft has released out-of-band (OOB) security updates to patch a critical-severity Windows Server Update Service (WSUS) vulnerability with publicly available proof-of-concept exploit code.
2026-05-24 12:02 UTC -
web:www.cisa.gov
Updated October 29, 2025: CISA has updated this Alert to include revised information on vulnerable product identification, potential threat activity detections, and additional resources. Microsoft released an update to address a critical remote code execution vulnerability impacting Windows Server Update Service (WSUS) in Windows Server (2012, 2016, 2019, 2022, and 2025), CVE -2025-59287
2026-05-24 12:02 UTC -
web:www.dbtsupport.com
The May 2026 Microsoft Patch Tuesday release includes security updates across supported Microsoft products and should be reviewed directly in the Microsoft Security Update Guide for the final CVE list, affected products, severity ratings, exploitability assessments, and any revised guidance.
2026-05-24 12:02 UTC -
web:www.notebookcheck.net
Microsoft April 2026 Patch Tuesday fixes 167 vulnerabilities, including an actively exploited SharePoint zero-day. Windows 11 KB5083769 and KB5082052 bring new builds and RDP security.
2026-05-24 12:02 UTC -
web:www.thehackerwire.com
CVE-2026-48207 details a critical deserialization of untrusted data vulnerability in Apache Fory PyFory, published on May 21, 2026 . With a CVSS score of 9.8, this flaw allows an attacker to bypass critical DeserializationPolicy validation hooks.
2026-05-24 12:02 UTC -
web:www.tomshardware.com
Installing this month's Windows Server security update has knocked some enterprise domain controllers into continuous reboot cycles, Microsoft confirmed in a release health dashboard entry.
2026-05-24 12:02 UTC -
web:4sysops.com
Starting in April 2026 , Windows updates will change the default Kerberos ticket issuance behavior to AES-SHA1 for accounts without explicit encryption settings, while RC4 can still be used where explicitly enabled. This change, driven by CVE - 2026 -20833, affects every Windows Server environment where service accounts or devices still rely on RC4. Any service account, NAS device, or legacy ...
2026-05-26 03:00 UTC -
web:guide.sonatype.com
Technical security analysis for CVE-2026-48207 . CVSS 8.4 severity. View CVSS vectors, CWE classifications, and exploit maturity ratings.
2026-05-26 03:00 UTC -
web:support.microsoft.com
This update for Windows 11, version 25H2 and 24H2 (KB5084597) incudes security improvements. To learn more about differences between security updates, optional non-security preview updates, out-of-band (OOB) updates, and continuous innovation, see Windows monthly updates explained. For information on Windows update terminology, see the different types of Windows software updates. To view the ...
2026-05-26 03:00 UTC -
web:vulmon.com
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.
2026-05-26 03:00 UTC -
web:www.computerworld.com
Each month, the team at Readiness analyzes the latest Patch Tuesday updates from Microsoft and provides detailed, actionable testing guidance. The company's Patch Tuesday release for February ...
2026-05-26 03:00 UTC -
web:www.securityweek.com
The initial vulnerability was exploited by Russia-linked APT28 in attacks against Ukraine and EU countries. Incomplete patch for a Windows SmartScreen and Windows Shell security prompts bypass created a new bug enabling zero-click attacks, Akamai reports. The initial vulnerability, tracked as CVE ...
2026-05-26 03:00 UTC -
web:www.techrepublic.com
Microsoft's April 2026 Patch Tuesday fixes 165 vulnerabilities, including two zero-days, in one of the company's largest monthly security updates.
2026-05-26 03:00 UTC -
web:www.tenable.com
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.
2026-05-26 03:00 UTC -
web:www.thehackerwire.com
An application is... How do I fix or mitigate CVE-2026-48207 ? To protect against CVE-2026-48207 , you should: (1) Apply the latest security patches from the vendor, (2) Check official security advisories for specific remediation steps, (3) Update affected software to the latest version, and (4) Monitor your systems for any signs of exploitation.
2026-05-26 03:00 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-48207.json.
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