GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration
Vulnerability from bitnami_vulndb
Published
2026-08-17 05:44
Modified
2026-08-17 06:10
Summary
Discourse: Duplicate lookup reveals restricted topic titles through canonicalized URLs
Details

Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, TopicLink.extract_from, TopicLink.ensure_entry_for, and TopicLink.duplicate_lookup do not consistently enforce Guardian.can_see? checks when processing internal links. An authenticated user can submit links to restricted topics, private messages, or hidden posts and receive canonicalized slugs or titles in the composer_messages duplicate_lookup response even though the targets are not visible to that user. This issue is fixed in versions 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0.

To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "Bitnami",
        "name": "discourse",
        "purl": "pkg:bitnami/discourse"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2026.1.6"
            },
            {
              "introduced": "2026.5.0"
            },
            {
              "fixed": "2026.5.2"
            },
            {
              "introduced": "2026.6.0"
            },
            {
              "fixed": "2026.6.1"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "severity": [
        {
          "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N",
          "type": "CVSS_V3"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-72722"
  ],
  "database_specific": {
    "cpes": [
      "cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*"
    ],
    "severity": "Medium"
  },
  "details": "Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, TopicLink.extract_from, TopicLink.ensure_entry_for, and TopicLink.duplicate_lookup do not consistently enforce Guardian.can_see? checks when processing internal links. An authenticated user can submit links to restricted topics, private messages, or hidden posts and receive canonicalized slugs or titles in the composer_messages duplicate_lookup response even though the targets are not visible to that user. This issue is fixed in versions 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0.",
  "id": "BIT-discourse-2026-72722",
  "modified": "2026-08-17T06:10:32.268Z",
  "published": "2026-08-17T05:44:22.723Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/discourse/discourse/commit/45abd925e46e8be40d2d047bced26628f26e4e31"
    },
    {
      "type": "WEB",
      "url": "https://github.com/discourse/discourse/commit/7d7ce546ac86e24a6512b321ace69fc52fe37bf4"
    },
    {
      "type": "WEB",
      "url": "https://github.com/discourse/discourse/commit/836a251d54a1004fb1c463a7d299b933b176191f"
    },
    {
      "type": "WEB",
      "url": "https://github.com/discourse/discourse/commit/e54ba27eacee0f14f315e510e287e7ac2e4bdb1a"
    },
    {
      "type": "WEB",
      "url": "https://github.com/discourse/discourse/pull/42091"
    },
    {
      "type": "WEB",
      "url": "https://github.com/discourse/discourse/pull/42092"
    },
    {
      "type": "WEB",
      "url": "https://github.com/discourse/discourse/pull/42093"
    },
    {
      "type": "WEB",
      "url": "https://github.com/discourse/discourse/pull/42094"
    },
    {
      "type": "WEB",
      "url": "https://github.com/discourse/discourse/security/advisories/GHSA-4fx9-5m29-83p4"
    },
    {
      "type": "WEB",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-72722"
    }
  ],
  "schema_version": "1.6.2",
  "summary": "Discourse: Duplicate lookup reveals restricted topic titles through canonicalized URLs"
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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