Vulnerability-Lookup

GHSA-27J2-H3M2-8237

Vulnerability from github – Published: 2026-09-10 06:31 – Updated: 2026-09-10 18:31

Details

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.

Severity

9.1 (Critical)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

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{
  "affected": [],
  "aliases": [
    "CVE-2026-84939"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-23"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-10T06:17:06Z",
    "severity": "CRITICAL"
  },
  "details": "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": "GHSA-27j2-h3m2-8237",
  "modified": "2026-09-10T18:31:40Z",
  "published": "2026-09-10T06:31:45Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-84939"
    },
    {
      "type": "WEB",
      "url": "https://lists.apache.org/thread/hrd7o2ylwkkswdyhyzllgqt0f80kyd5y"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2026/09/08/2"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-84939 (GCVE-0-2026-84939)

Vulnerability from cvelistv5 – Published: 2026-09-10 05:07 – Updated: 2026-09-10 15:58

Title

Apache FreeMarker, Apache FreeMarker: A malformed locale may be exploitable for path traversal attacks

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.

Severity

9.1 (Critical)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

SSVC

Exploitation: none Automatable: yes Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-10 15:57 UTC

CWE

CWE-23 - Relative path traversal

Assigner

apache mitre root

References

2 references

URL	Tags
https://lists.apache.org/thread/hrd7o2ylwkkswdyhy…	vendor-advisory
http://www.openwall.com/lists/oss-security/2026/09/08/2

Impacted products

1 product

Vendor	Product	Version
Apache Software Foundation	Apache FreeMarker	Affected: 2.2.0 , ≤ 2.3.34 (semver) Unaffected: 2.3.35 (semver)

Show details on NVD website

JSON

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

GHSA-27J2-H3M2-8237

CVE-2026-84939 (GCVE-0-2026-84939)

Tags

Sightings

Nomenclature