CVE-2026-34481

Apache Log4j's JsonTemplateLayout https://logging.apache.org/log4j/2.x/manual/json-template-layout.html , in versions up to and including 2.25.3, produces invalid JSON output when log events contain non-finite floating-point values (NaN, Infinity, or -Infinity), which are prohibited by RFC 8259. This may cause downstream log processing systems to reject or fail to index affected records. An attacker can exploit this issue only if both of the following conditions are met: * The application uses JsonTemplateLayout. * The application logs a MapMessage containing an attacker-controlled floating-point value. Users are advised to upgrade to Apache Log4j JSON Template Layout 2.25.4, which corrects this issue.

CVSS

No CVSS.

References

Link	Resource
https://github.com/apache/logging-log4j2/pull/4080
https://lists.apache.org/thread/n34zdv00gbkdbzt2rx9rf5mqz6lhopcv
https://logging.apache.org/cyclonedx/vdr.xml
https://logging.apache.org/log4j/2.x/manual/json-template-layout.html
https://logging.apache.org/security.html#CVE-2026-34481
http://www.openwall.com/lists/oss-security/2026/04/10/10

Configurations

No configuration.

History

10 Apr 2026, 17:17

Type	Values Removed	Values Added
References		() http://www.openwall.com/lists/oss-security/2026/04/10/10 -

10 Apr 2026, 16:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-10 16:16

Updated : 2026-04-13 15:02

NVD link : CVE-2026-34481

Mitre link : CVE-2026-34481

CVE.ORG link : CVE-2026-34481

JSON object : View

Products Affected

No product.

CWE

CWE-116

Improper Encoding or Escaping of Output

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