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TI-2026-76338 Aliases CVE-2026-71253GHSA-66gj-8qvf-qvfh

Apache Johnzon ClassConverter loads attacker-named classes from JSON

Priority MEDIUM 49CWE-470Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 1 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat.

Summary

Apache Johnzon versions from 1.0.0 before 1.3.1 and from 2.0.0 before 2.2.0 are affected. ClassConverter uses unsafe reflection (CWE-470), loading and static-initializing a class whose name comes from untrusted JSON. An unauthenticated remote attacker can trigger this by sending crafted JSON, with high impact to confidentiality, integrity and availability.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection') vulnerability in Apache Johnzon. ClassConverter loads & static-initializes an attacker-named class from untrusted JSON. This issue affects Apache Johnzon: from 1.0.0 before 2.2.0. Users are recommended to upgrade to version 1.3.1 (javax namespace) or 2.2.0 (jakarta specification namespace), which fixes the issue.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0038 32nd percentileScored 2026-11-07
Fix Partial Apache Johnzon (Apache Software Foundation): 2.2.0, 1.3.1Red Hat: 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
ApacheApache Johnzon2.0.0 to before 2.2.0; 1.0.0 to before 1.3.12.2.0, 1.3.1Patch availableCNA
  • Apache Johnzon VendorApache Affected 2.0.0 to before 2.2.0; 1.0.0 to before 1.3.1 Fixed in 2.2.0, 1.3.1 Patch available CNA

Remediation

Upgrade Apache Johnzon to 1.3.1 for the javax namespace or to 2.2.0 for the jakarta namespace. Red Hat lists Red Hat Fuse 7 as affected with no fix planned.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA Apache Johnzon (Apache Software Foundation) Fixed in 2.2.0, 1.3.1

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Fuse 7AffectedNo fix planned: Out of support scope

Timeline

  1. 2026-10-19 Threatist record created from CVE-2026-71253
  2. 2026-10-19 Alias added: GHSA-66gj-8qvf-qvfh
  3. 2026-10-20 Affected versions changed · Red Hat
  4. 2026-10-20 CVSS score added · Red Hat
  5. 2026-10-20 CVSS score added · CISA ADP
  6. 2026-10-20 CISA SSVC decision points changed
  7. 2026-10-20 Priority changed: LOW → MEDIUM
  8. 2026-10-21 EPSS moved to the 50th–90th percentile
  9. 2026-10-25 EPSS moved to the below the 50th percentile

References

Patch 2

Advisory 1

  • TI-2025-18529 Apache Tomcat: Potential RCE and/or information disclosure and/or information corruption with partial PUT KEVCVSS 3.1CRITICAL 10.0
  • TI-2024-30292 Apache OFBiz: Confused controller-view authorization logic (forced browsing) KEVCVSS 3.1CRITICAL 9.8
  • TI-2024-26062 Apache OFBiz: Unauthenticated endpoint could allow execution of screen rendering code KEVCVSS 3.1CRITICAL 9.8
  • TI-2024-21190 Apache OFBiz: Path traversal leading to RCE KEVCVSS 3.1CRITICAL 9.8
  • TI-2024-18186 Apache HugeGraph-Server: Command execution in gremlin KEVCVSS 3.1CRITICAL 9.8
  • TI-2023-25106 Deserialization of untrusted data in Apache ActiveMQ KEVCVSS 3.1CRITICAL 10.0
See all 4053 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences