CVE-2026-71253

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.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/apache/johnzon/commit/91e7b0d21d08d138944e2570691939739422a3d6
https://github.com/apache/johnzon/commit/dd3d00634c746a2173a2518e882e85e8a151bf30
https://lists.apache.org/thread.html/3vgm1yo2sn9yhkvvs9lc4ro01vl3zt68

Configurations

No configuration.

History

20 Oct 2026, 20:17

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.8

19 Oct 2026, 11:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-19 11:17

Updated : 2026-10-20 20:17

NVD link : CVE-2026-71253

Mitre link : CVE-2026-71253

CVE.ORG link : CVE-2026-71253

JSON object : View

Products Affected

No product.

CWE

CWE-470

Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection')

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