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2 vulnerabilities found for Apache Log4j JSON Template Layout by Apache Software Foundation

CVE-2026-34481 (GCVE-0-2026-34481)

Vulnerability from nvd – Published: 2026-04-10 15:43 – Updated: 2026-04-10 17:41
VLAI?
Title
Apache Log4j JSON Template Layout: Improper serialization of non-finite floating-point values in JsonTemplateLayout
Summary
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.
Severity ?
6.3 (Medium)
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
CWE
  • CWE-116 - Improper Encoding or Escaping of Output
Assigner
References
Impacted products
Vendor Product Version
Apache Software Foundation Apache Log4j JSON Template Layout Affected: 2.14.0 , < 2.25.4 (maven)
Affected: 3.0.0-alpha1 , ≤ 3.0.0-beta3 (maven)
    cpe:2.3:a:apache:log4j_layout_template_json:*:*:*:*:*:*:*:*
 Create a notification for this product.
Credits
Ap4sh (Samy Medjahed) and Ethicxz (Eliott Laurie)
Show details on NVD website
To clipboard 

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CVE-2026-34481 (GCVE-0-2026-34481)

Vulnerability from cvelistv5 – Published: 2026-04-10 15:43 – Updated: 2026-04-10 17:41
VLAI?
Title
Apache Log4j JSON Template Layout: Improper serialization of non-finite floating-point values in JsonTemplateLayout
Summary
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.
Severity ?
6.3 (Medium)
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
CWE
  • CWE-116 - Improper Encoding or Escaping of Output
Assigner
References
Impacted products
Vendor Product Version
Apache Software Foundation Apache Log4j JSON Template Layout Affected: 2.14.0 , < 2.25.4 (maven)
Affected: 3.0.0-alpha1 , ≤ 3.0.0-beta3 (maven)
    cpe:2.3:a:apache:log4j_layout_template_json:*:*:*:*:*:*:*:*
 Create a notification for this product.
Credits
Ap4sh (Samy Medjahed) and Ethicxz (Eliott Laurie)
Show details on NVD website
To clipboard 

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