CVE-2026-71253CWE-470

CVE-2026-71253

Critical · published October 19, 2026

CVSS v3.1
9.8
EPSS
1%
Percentile
50.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00654 · 50.7th percentile
Weakness
CWE-470 · Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection')
Published
2026-10-19T15:17Z
References (3)
https://github.com/apache/johnzon/commit/91e7b0d21d08d138944e2570691939739422a3d6 · [email protected]https://github.com/apache/johnzon/commit/dd3d00634c746a2173a2518e882e85e8a151bf30 · [email protected]https://lists.apache.org/thread.html/3vgm1yo2sn9yhkvvs9lc4ro01vl3zt68 · [email protected]
EPSS history
Timeline
  • 21 OCT 03:31Z
    EPSS moved — → 0%
    epss
  • 19 OCT 10:36Z
    Apache Johnzon: ClassConverter loads & static-initializes an attacker-named class from untrusted JSON
    cvelistv5
  • 19 OCT 10:36Z
    Apache Johnzon: ClassConverter loads & static-initializes an attacker-named class from untrusted JSON
    cvelistv5