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FKIE_CVE-2026-84939

Vulnerability from fkie_nvd - Published: 2026-09-10 06:17 - Updated: 2026-09-11 13:06
Severity
9.1 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Summary
Path traversal vulnerability in Apache FreeMarker template loading mechanism, if the attacker can specify an arbitrary malformed locale identifier to FreeMarker, and the localized lookup configuration setting is enabled (it's by default enabled). This issue affects Apache FreeMarker from 2.2.0 through 2.3.34. Users are recommended to upgrade to version 2.3.35. Disabling localized lookup in previous versions also mitigates this. Note that even in versions affected by this vulnerability, the files that can be loaded remain restricted by the TemplateLoader that FreeMarker is configured to use. In particular, FileTemplateLoader prevents attempts to traverse outside the baseDir specified in its constructor. Other TemplateLoader implementations may allow access outside their designated base directory, but they are still constrained by the underlying storage mechanism—for example, a loader wrapping a Java class loader can only access resources that the class loader can load, while one wrapping a web application context can only access resources available through that context.
References
security@apache.orghttps://lists.apache.org/thread/hrd7o2ylwkkswdyhyzllgqt0f80kyd5yMailing List, Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108http://www.openwall.com/lists/oss-security/2026/09/08/2Mailing List, Third Party Advisory
Impacted products
Vendor Product Version
apache freemarker *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "collectionURL": "https://repo.maven.apache.org/maven2",
          "defaultStatus": "unaffected",
          "packageName": "org.freemarker:freemarker",
          "packageURL": "pkg:maven/org.freemarker/freemarker",
          "product": "Apache FreeMarker",
          "vendor": "Apache Software Foundation",
          "versions": [
            {
              "lessThanOrEqual": "2.3.34",
              "status": "affected",
              "version": "2.2.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "2.3.35",
              "versionType": "semver"
            }
          ]
        },
        {
          "collectionURL": "https://repo.maven.apache.org/maven2",
          "defaultStatus": "unaffected",
          "packageName": "org.freemarker:freemarker-gae",
          "packageURL": "pkg:maven/org.freemarker/freemarker-gae",
          "product": "Apache FreeMarker",
          "vendor": "Apache Software Foundation",
          "versions": [
            {
              "lessThanOrEqual": "2.3.34",
              "status": "affected",
              "version": "2.2.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "2.3.35",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "security@apache.org"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:apache:freemarker:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "8B75C028-6B48-4369-9E9B-409E6930D680",
              "versionEndExcluding": "2.3.35",
              "versionStartIncluding": "2.2",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Path traversal vulnerability in Apache FreeMarker template loading mechanism, if the attacker can specify an arbitrary malformed locale identifier to FreeMarker, and the localized lookup configuration setting is enabled (it\u0027s by default enabled).\n\nThis issue affects Apache FreeMarker from 2.2.0 through 2.3.34.\n\nUsers are recommended to upgrade to version 2.3.35. Disabling localized lookup in previous versions also mitigates this.\n\nNote that even in versions affected by this vulnerability, the files that can be loaded remain restricted by the TemplateLoader that FreeMarker is configured to use. In particular, FileTemplateLoader prevents attempts to traverse outside the baseDir specified in its constructor. Other TemplateLoader implementations may allow access outside their designated base directory, but they are still constrained by the underlying storage mechanism\u2014for example, a loader wrapping a Java class loader can only access resources that the class loader can load, while one wrapping a web application context can only access resources available through that context."
    }
  ],
  "id": "CVE-2026-84939",
  "lastModified": "2026-09-11T13:06:56.423",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 9.1,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.2,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-84939",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-10T15:57:22.150692Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-10T06:17:06.460",
  "references": [
    {
      "source": "security@apache.org",
      "tags": [
        "Mailing List",
        "Vendor Advisory"
      ],
      "url": "https://lists.apache.org/thread/hrd7o2ylwkkswdyhyzllgqt0f80kyd5y"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Mailing List",
        "Third Party Advisory"
      ],
      "url": "http://www.openwall.com/lists/oss-security/2026/09/08/2"
    }
  ],
  "sourceIdentifier": "security@apache.org",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-23"
        }
      ],
      "source": "security@apache.org",
      "type": "Secondary"
    }
  ]
}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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