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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-34481 Detail

Description

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  Apache Software Foundation
CVSS-B 6.3 MEDIUM
Vector:  CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
http://www.openwall.com/lists/oss-security/2026/04/10/10 CVE Mailing List  Third Party Advisory 
https://github.com/apache/logging-log4j2/pull/4080 Apache Software Foundation Issue Tracking 
https://lists.apache.org/thread/n34zdv00gbkdbzt2rx9rf5mqz6lhopcv Apache Software Foundation Mailing List  Vendor Advisory 
https://logging.apache.org/cyclonedx/vdr.xml Apache Software Foundation Product 
https://logging.apache.org/log4j/2.x/manual/json-template-layout.html Apache Software Foundation Technical Description 
https://logging.apache.org/security.html#CVE-2026-34481 Apache Software Foundation Vendor Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-116 Improper Encoding or Escaping of Output Apache Software Foundation  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

3 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-34481
NVD Published Date:
04/10/2026
NVD Last Modified:
04/24/2026
Source:
Apache Software Foundation