Vulnerability-Lookup

Vulnerability from bitnami_vulndb

Published

2026-02-02 08:42

Modified

2026-09-08 08:34

Summary

Discourse allows script execution in uploaded HTML/XML files on S3

Details

Discourse is an open source discussion platform. A vulnerability present in versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0 affects anyone who uses S3 for uploads. While scripts may be executed, they will only be run in the context of the S3/CDN domain, with no site credentials. Versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0 fix the issue. As a workaround, disallow html or xml files for uploads in authorized_extensions. For existing html xml uploads, site owners can consider deleting them.

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "Bitnami",
        "name": "discourse",
        "purl": "pkg:bitnami/discourse"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.5.4"
            },
            {
              "introduced": "2025.11.0"
            },
            {
              "fixed": "2025.11.2"
            },
            {
              "introduced": "2025.12.0"
            },
            {
              "fixed": "2025.12.1"
            },
            {
              "introduced": "2026.1.0"
            },
            {
              "fixed": "2026.1.0"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "severity": [
        {
          "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
          "type": "CVSS_V3"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-66488"
  ],
  "database_specific": {
    "cpes": [
      "cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*"
    ],
    "severity": "Medium"
  },
  "details": "Discourse is an open source discussion platform. A vulnerability present in versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0 affects anyone who uses S3 for uploads. While scripts may be executed, they will only be run in the context of the S3/CDN domain, with no site credentials. Versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0 fix the issue. As a workaround, disallow html or xml files for uploads in authorized_extensions. For existing html xml uploads, site owners can consider deleting them.",
  "id": "BIT-discourse-2025-66488",
  "modified": "2026-09-08T08:34:36.952Z",
  "published": "2026-02-02T08:42:08.194Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/discourse/discourse/security/advisories/GHSA-68jp-3934-62rx"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-66488"
    }
  ],
  "schema_version": "1.6.2",
  "summary": "Discourse allows script execution in uploaded HTML/XML files on S3"
}

CVE-2025-66488 (GCVE-0-2025-66488)

Vulnerability from cvelistv5 – Published: 2026-01-28 18:15 – Updated: 2026-01-28 19:29

Title

Discourse allows script execution in uploaded HTML/XML files on S3

Summary

Severity

4.6 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-01-28 18:28 UTC

CWE

CWE-116 - Improper Encoding or Escaping of Output

Assigner

GitHub_M mitre root

References

1 reference

URL	Tags
https://github.com/discourse/discourse/security/a…	x_refsource_CONFIRM

Impacted products

1 product

Vendor	Product	Version
discourse	discourse	Affected: < 3.5.4 Affected: >= 2025.11.0-latest, < 2025.11.2 Affected: >= 2025.12.0-latest, < 2025.12.1 Affected: >= 2026.1.0-latest, < 2026.1.0

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2025-66488",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-01-28T18:28:39.719089Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-01-28T18:28:50.363Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "discourse",
          "vendor": "discourse",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 3.5.4"
            },
            {
              "status": "affected",
              "version": "\u003e= 2025.11.0-latest, \u003c 2025.11.2"
            },
            {
              "status": "affected",
              "version": "\u003e= 2025.12.0-latest, \u003c 2025.12.1"
            },
            {
              "status": "affected",
              "version": "\u003e= 2026.1.0-latest, \u003c 2026.1.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Discourse is an open source discussion platform. A vulnerability present in versions prior to 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0 affects anyone who uses S3 for uploads. While scripts may be executed, they will only be run in the context of the S3/CDN domain, with no site credentials. Versions 3.5.4, 2025.11.2, 2025.12.1, and 2026.1.0 fix the issue. As a workaround, disallow html or xml files for uploads in authorized_extensions. For existing html xml uploads, site owners can consider deleting them."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "LOW",
            "baseScore": 4.6,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "LOW",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:L",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-116",
              "description": "CWE-116: Improper Encoding or Escaping of Output",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-01-28T19:29:11.123Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/discourse/discourse/security/advisories/GHSA-68jp-3934-62rx",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/discourse/discourse/security/advisories/GHSA-68jp-3934-62rx"
        }
      ],
      "source": {
        "advisory": "GHSA-68jp-3934-62rx",
        "discovery": "UNKNOWN"
      },
      "title": "Discourse allows script execution in uploaded HTML/XML files on S3"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2025-66488",
    "datePublished": "2026-01-28T18:15:52.902Z",
    "dateReserved": "2025-12-02T22:44:04.706Z",
    "dateUpdated": "2026-01-28T19:29:11.123Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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Vulnerability from bitnami_vulndb

CVE-2025-66488 (GCVE-0-2025-66488)

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