Apache Log4j JSON Template Layout: Improper serialization of non-finite floating-point values in JsonTemplateLayout (Apache Software Foundation Apache Log4j JSON Template Layout)

CVE-2026-34481
MEDIUM 6.3

En bref

Source
NVD
EPSS
EPSS 0.69 % · centile 53 ()
État
PUBLISHED
Publiée
Mise à jour
Attribuée par
apache
Statut NVD
Modified

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, or logs an object directly (e.g., via Logger.info(Object), which wraps it in an ObjectMessage), where the message contains an attacker-controlled floating-point value. Users are advised to upgrade to Apache Log4j JSON Template Layout 2.25.4, which corrects this issue. Note: The fix released in version 2.25.4 did not cover all affected code paths. CVE-2026-49844 was assigned to the remaining issue, which concerns the MapMessage.asJson() serialization in Apache Log4j API and is fixed in versions 2.25.5 and 2.26.1.

Faiblesses (CWE)

  • CWE-116 — Encodage ou échappement incorrect de la sortie

Références

Scores

VersionScoreVecteurÉvalué par
CVSS 4.0MEDIUM 6.3CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:Napache
CVSS 4.0MEDIUM 6.3CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XNVD · security@apache.org (Secondary)
CVSS 3.1HIGH 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:NNVD · nvd@nist.gov (Primary)

Avis

Références européennes

Avis du CERT-FR

Configurations affectées (CPE NVD)

Produits affectés

ProduitVersions
Apache Software Foundation · Apache Log4j JSON Template Layoutaffected 2.14.0 < 2.25.4 ; affected 3.0.0-alpha1 ≤ 3.0.0-beta3

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD