{"id":"CVE-2026-71253","title":"Apache Johnzon: ClassConverter loads & static-initializes an attacker-named class from untrusted JSON","summary":"Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection') vulnerability in Apache Johnzon.\n\n\n\nClassConverter loads & static-initializes an attacker-named class from untrusted JSON.\n\n\n\n\nThis issue affects Apache J…","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cvssSource":"adp","cwe":["CWE-470"],"vendor":"Apache Software Foundation","product":"org.apache.johnzon:johnzon-mapper","affected":["org.apache.johnzon:johnzon-mapper >= 2.0.0 < 2.2.0","org.apache.johnzon:johnzon-mapper >= 1.0.0 < 1.3.1"],"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"total","timestamp":"2026-10-20T19:34:08.742206Z"},"published":"2026-10-19","updated":"2026-10-20","sourceUpdated":"2026-10-20T19:34:25.835Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-71253","references":[{"url":"https://github.com/apache/johnzon/commit/dd3d00634c746a2173a2518e882e85e8a151bf30"},{"url":"https://github.com/apache/johnzon/commit/91e7b0d21d08d138944e2570691939739422a3d6"},{"url":"https://lists.apache.org/thread.html/3vgm1yo2sn9yhkvvs9lc4ro01vl3zt68"}],"tags":["cve.org"],"epss":0.0038,"epssPercentile":0.31802,"ingestedAt":"2026-10-19T12:27:23.813Z","slug":"CVE-2026-71253","body":"## Overview\n\nUse of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection') vulnerability in Apache Johnzon.\n\n\n\nClassConverter loads & static-initializes an attacker-named class from untrusted JSON.\n\n\n\n\nThis issue affects Apache Johnzon: from 1.0.0 before 2.2.0.\n\n\n\nUsers are recommended to upgrade to version 1.3.1 (javax namespace) or 2.2.0 (jakarta specification namespace), which fixes the issue.\n\n## Affected\n\n- `org.apache.johnzon:johnzon-mapper >= 2.0.0 < 2.2.0`\n- `org.apache.johnzon:johnzon-mapper >= 1.0.0 < 1.3.1`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"midnight","depthScore":54,"depthScoreParts":{"impact":53.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":226121,"id":"CVE-2026-71253","ts":1792527517211,"field":"cvss","old":null,"new":"9.8"},{"seq":226120,"id":"CVE-2026-71253","ts":1792527517211,"field":"severity","old":"none","new":"critical"}]}