{
  "schemaVersion": 1,
  "attribution": [
    {
      "source": "CISA Known Exploited Vulnerabilities",
      "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog",
      "licence": "US government work"
    },
    {
      "source": "GitHub Advisory Database",
      "url": "https://github.com/advisories",
      "licence": "CC BY 4.0"
    },
    {
      "source": "Have I Been Pwned",
      "url": "https://haveibeenpwned.com/",
      "licence": "CC BY 4.0"
    },
    {
      "source": "CVE Program (CVE records)",
      "url": "https://www.cve.org/Legal/TermsOfUse",
      "licence": "CVE Terms of Use",
      "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.",
      "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy."
    },
    {
      "source": "FIRST EPSS",
      "url": "https://www.first.org/epss/",
      "licence": "free to use; FIRST requests attribution"
    }
  ],
  "record": {
    "id": "CVE-2026-49844",
    "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2026-49844",
    "idYear": 2026,
    "status": "PUBLISHED",
    "publishedAt": "2026-07-10T21:14:59.111Z",
    "updatedAt": "2026-09-17T18:37:58.088Z",
    "importedAt": "2026-10-24T01:58:14.884Z",
    "snapshot": {
      "id": "cve_2026-10-24_midnight_baseline",
      "at": "2026-10-24T00:00:00.000Z",
      "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z"
    },
    "facts": {
      "title": "Apache Log4j API: Improper serialization of non-finite floating-point values in MapMessage.asJson()",
      "summary": "Improper encoding of non-finite floating-point values during MapMessage JSON serialization in Apache Log4j API produces output that is not valid JSON. This issue affects Apache Log4j API versions 2.13.1 through 2.25.4 and version 2.26.0.\n\nThe fix for CVE-2026-34481 did not cover all code paths: when a MapMessage contains a non-finite IEEE 754 value (NaN, Infinity, or -Infinity), MapMessage.asJson() emits the corresponding bare token. RFC 8259 does not permit these tokens, so a conformant parser rejects the resulting document.\n\nThe defect is reachable only when both of the following conditions hold:\n\n  *  The application uses the  message resolver https://logging.apache.org/log4j/2.x/manual/json-template-layout.html#event-template-resolver-message  of JsonTemplateLayout or any other layout that relies on MapMessage.asJson() or MapMessage.getFormattedMessage(new String[]{\"JSON\"}).\n  *  The application logs a MapMessage that contains an attacker-controlled floating-point value.\n\n\nAn attacker who can supply a non-finite value can cause the affected layout to emit malformed JSON, which may corrupt the enclosing log record or disrupt downstream log ingestion and parsing.\n\nUsers are advised to upgrade to Apache Log4j API 2.25.5 or 2.26.1, both of which emit RFC 8259-compliant JSON for non-finite values.",
      "affected": [
        {
          "vendor": "Apache Software Foundation",
          "product": "Apache Log4j API",
          "packageName": "org.apache.logging.log4j:log4j-api",
          "collectionURL": "https://repo.maven.apache.org/maven2",
          "defaultStatus": "unaffected",
          "versions": [
            {
              "version": "2.13.1",
              "status": "affected",
              "versionType": "maven",
              "lessThan": "2.25.5"
            },
            {
              "version": "2.26.0",
              "status": "affected",
              "versionType": "maven",
              "lessThan": "2.26.1"
            },
            {
              "version": "3.0.0-alpha1",
              "status": "affected",
              "versionType": "maven",
              "lessThanOrEqual": "3.0.0-beta2"
            }
          ]
        }
      ]
    }
  }
}