FKIE_CVE-2026-34481

Vulnerability from fkie_nvd - Published: 2026-04-10 16:16 - Updated: 2026-04-24 18:24
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
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.
References
security@apache.orghttps://github.com/apache/logging-log4j2/pull/4080Issue Tracking
security@apache.orghttps://lists.apache.org/thread/n34zdv00gbkdbzt2rx9rf5mqz6lhopcvMailing List, Vendor Advisory
security@apache.orghttps://logging.apache.org/cyclonedx/vdr.xmlProduct
security@apache.orghttps://logging.apache.org/log4j/2.x/manual/json-template-layout.htmlTechnical Description
security@apache.orghttps://logging.apache.org/security.html#CVE-2026-34481Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108http://www.openwall.com/lists/oss-security/2026/04/10/10Mailing List, Third Party Advisory
Impacted products
Vendor Product Version
apache log4j *
apache log4j 3.0.0
apache log4j 3.0.0
apache log4j 3.0.0
apache log4j 3.0.0
apache log4j 3.0.0
apache log4j 3.0.0
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{
  "configurations": [
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              "versionEndExcluding": "2.25.4",
              "versionStartIncluding": "2.14.0",
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  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Apache Log4j\u0027s  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.\n\nAn attacker can exploit this issue only if both of the following conditions are met:\n\n  *  The application uses JsonTemplateLayout.\n  *  The application logs a MapMessage containing an attacker-controlled floating-point value.\n\n\nUsers are advised to upgrade to Apache Log4j JSON Template Layout 2.25.4, which corrects this issue."
    }
  ],
  "id": "CVE-2026-34481",
  "lastModified": "2026-04-24T18:24:14.900",
  "metrics": {
    "cvssMetricV31": [
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        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
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        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
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    "cvssMetricV40": [
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          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
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          "attackRequirements": "PRESENT",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 6.3,
          "baseSeverity": "MEDIUM",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "NONE",
          "providerUrgency": "NOT_DEFINED",
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          "valueDensity": "NOT_DEFINED",
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          "vulnIntegrityImpact": "NONE",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
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  "published": "2026-04-10T16:16:31.663",
  "references": [
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      "tags": [
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}


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