CVE-2026-72723 (GCVE-0-2026-72723)

Vulnerability from cvelistv5 – Published: 2026-08-10 15:56 – Updated: 2026-08-10 21:11
VLAI
Title
Discourse: Anonymous sidebar serialization exposes descriptions of category-restricted tags
Summary
Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, SiteSerializer.anonymous_default_navigation_menu_tags serializes tags from SiteSetting.default_navigation_menu_tags without applying DiscourseTagging.filter_visible for the anonymous viewer. An unauthenticated user can retrieve restricted tag names and descriptions through /site.json when those tags are limited by inaccessible categories, category tag groups, or tag-group permissions. This issue is fixed in versions 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
Assigner
References
Impacted products
Vendor Product Version
discourse discourse Affected: < 2026.1.6
Affected: >= 2026.5.0-latest, < 2026.5.2
Affected: >= 2026.6.0-latest, < 2026.6.1
Affected: >= 2026.7.0-latest, < 2026.7.0
Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-72723",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-10T19:02:43.987708Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-10T21:11:02.865Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "discourse",
          "vendor": "discourse",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 2026.1.6"
            },
            {
              "status": "affected",
              "version": "\u003e= 2026.5.0-latest, \u003c 2026.5.2"
            },
            {
              "status": "affected",
              "version": "\u003e= 2026.6.0-latest, \u003c 2026.6.1"
            },
            {
              "status": "affected",
              "version": "\u003e= 2026.7.0-latest, \u003c 2026.7.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, SiteSerializer.anonymous_default_navigation_menu_tags serializes tags from SiteSetting.default_navigation_menu_tags without applying DiscourseTagging.filter_visible for the anonymous viewer. An unauthenticated user can retrieve restricted tag names and descriptions through /site.json when those tags are limited by inaccessible categories, category tag groups, or tag-group permissions. This issue is fixed in versions 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-862",
              "description": "CWE-862: Missing Authorization",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-10T15:56:53.723Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/discourse/discourse/security/advisories/GHSA-4p6q-h74v-5j7p",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/discourse/discourse/security/advisories/GHSA-4p6q-h74v-5j7p"
        },
        {
          "name": "https://github.com/discourse/discourse/pull/42091",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/discourse/discourse/pull/42091"
        },
        {
          "name": "https://github.com/discourse/discourse/pull/42092",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/discourse/discourse/pull/42092"
        },
        {
          "name": "https://github.com/discourse/discourse/pull/42093",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/discourse/discourse/pull/42093"
        },
        {
          "name": "https://github.com/discourse/discourse/pull/42094",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/discourse/discourse/pull/42094"
        },
        {
          "name": "https://github.com/discourse/discourse/commit/0248e9ca82d0493037a9ca04d73904ccfad795f9",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/discourse/discourse/commit/0248e9ca82d0493037a9ca04d73904ccfad795f9"
        },
        {
          "name": "https://github.com/discourse/discourse/commit/03444ddb74d535dda557350f4c5800a6ec2669d7",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/discourse/discourse/commit/03444ddb74d535dda557350f4c5800a6ec2669d7"
        },
        {
          "name": "https://github.com/discourse/discourse/commit/900f51c147913f667e64484c2f2dd48c723314ac",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/discourse/discourse/commit/900f51c147913f667e64484c2f2dd48c723314ac"
        },
        {
          "name": "https://github.com/discourse/discourse/commit/da84c677213cac3b024e753f180f45472b89efde",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/discourse/discourse/commit/da84c677213cac3b024e753f180f45472b89efde"
        }
      ],
      "source": {
        "advisory": "GHSA-4p6q-h74v-5j7p",
        "discovery": "UNKNOWN"
      },
      "title": "Discourse: Anonymous sidebar serialization exposes descriptions of category-restricted tags"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-72723",
    "datePublished": "2026-08-10T15:56:53.723Z",
    "dateReserved": "2026-08-10T13:48:09.545Z",
    "dateUpdated": "2026-08-10T21:11:02.865Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-72723\",\"sourceIdentifier\":\"security-advisories@github.com\",\"published\":\"2026-08-10T16:19:49.667\",\"lastModified\":\"2026-08-10T21:17:23.923\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, SiteSerializer.anonymous_default_navigation_menu_tags serializes tags from SiteSetting.default_navigation_menu_tags without applying DiscourseTagging.filter_visible for the anonymous viewer. An unauthenticated user can retrieve restricted tag names and descriptions through /site.json when those tags are limited by inaccessible categories, category tag groups, or tag-group permissions. This issue is fixed in versions 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0.\"}],\"affected\":[{\"source\":\"security-advisories@github.com\",\"affectedData\":[{\"vendor\":\"discourse\",\"product\":\"discourse\",\"versions\":[{\"version\":\"\u003c 2026.1.6\",\"status\":\"affected\"},{\"version\":\"\u003e= 2026.5.0-latest, \u003c 2026.5.2\",\"status\":\"affected\"},{\"version\":\"\u003e= 2026.6.0-latest, \u003c 2026.6.1\",\"status\":\"affected\"},{\"version\":\"\u003e= 2026.7.0-latest, \u003c 2026.7.0\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"3.1\",\"vectorString\":\"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N\",\"baseScore\":5.3,\"baseSeverity\":\"MEDIUM\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"LOW\",\"integrityImpact\":\"NONE\",\"availabilityImpact\":\"NONE\"},\"exploitabilityScore\":3.9,\"impactScore\":1.4}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-08-10T19:02:43.987708Z\",\"id\":\"CVE-2026-72723\",\"options\":[{\"exploitation\":\"none\"},{\"automatable\":\"yes\"},{\"technicalImpact\":\"partial\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-862\"}]}],\"references\":[{\"url\":\"https://github.com/discourse/discourse/commit/0248e9ca82d0493037a9ca04d73904ccfad795f9\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/discourse/discourse/commit/03444ddb74d535dda557350f4c5800a6ec2669d7\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/discourse/discourse/commit/900f51c147913f667e64484c2f2dd48c723314ac\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/discourse/discourse/commit/da84c677213cac3b024e753f180f45472b89efde\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/discourse/discourse/pull/42091\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/discourse/discourse/pull/42092\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/discourse/discourse/pull/42093\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/discourse/discourse/pull/42094\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/discourse/discourse/security/advisories/GHSA-4p6q-h74v-5j7p\",\"source\":\"security-advisories@github.com\"}]}}",
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-72723\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"yes\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-08-10T19:02:43.987708Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-08-10T19:02:48.876Z\"}}], \"cna\": {\"title\": \"Discourse: Anonymous sidebar serialization exposes descriptions of category-restricted tags\", \"source\": {\"advisory\": \"GHSA-4p6q-h74v-5j7p\", \"discovery\": \"UNKNOWN\"}, \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 5.3, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"MEDIUM\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N\", \"integrityImpact\": \"NONE\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"NONE\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"LOW\"}}], \"affected\": [{\"vendor\": \"discourse\", \"product\": \"discourse\", \"versions\": [{\"status\": \"affected\", \"version\": \"\u003c 2026.1.6\"}, {\"status\": \"affected\", \"version\": \"\u003e= 2026.5.0-latest, \u003c 2026.5.2\"}, {\"status\": \"affected\", \"version\": \"\u003e= 2026.6.0-latest, \u003c 2026.6.1\"}, {\"status\": \"affected\", \"version\": \"\u003e= 2026.7.0-latest, \u003c 2026.7.0\"}]}], \"references\": [{\"url\": \"https://github.com/discourse/discourse/security/advisories/GHSA-4p6q-h74v-5j7p\", \"name\": \"https://github.com/discourse/discourse/security/advisories/GHSA-4p6q-h74v-5j7p\", \"tags\": [\"x_refsource_CONFIRM\"]}, {\"url\": \"https://github.com/discourse/discourse/pull/42091\", \"name\": \"https://github.com/discourse/discourse/pull/42091\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/discourse/discourse/pull/42092\", \"name\": \"https://github.com/discourse/discourse/pull/42092\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/discourse/discourse/pull/42093\", \"name\": \"https://github.com/discourse/discourse/pull/42093\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/discourse/discourse/pull/42094\", \"name\": \"https://github.com/discourse/discourse/pull/42094\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/discourse/discourse/commit/0248e9ca82d0493037a9ca04d73904ccfad795f9\", \"name\": \"https://github.com/discourse/discourse/commit/0248e9ca82d0493037a9ca04d73904ccfad795f9\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/discourse/discourse/commit/03444ddb74d535dda557350f4c5800a6ec2669d7\", \"name\": \"https://github.com/discourse/discourse/commit/03444ddb74d535dda557350f4c5800a6ec2669d7\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/discourse/discourse/commit/900f51c147913f667e64484c2f2dd48c723314ac\", \"name\": \"https://github.com/discourse/discourse/commit/900f51c147913f667e64484c2f2dd48c723314ac\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/discourse/discourse/commit/da84c677213cac3b024e753f180f45472b89efde\", \"name\": \"https://github.com/discourse/discourse/commit/da84c677213cac3b024e753f180f45472b89efde\", \"tags\": [\"x_refsource_MISC\"]}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"Discourse is an open-source discussion platform. Prior to 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0, SiteSerializer.anonymous_default_navigation_menu_tags serializes tags from SiteSetting.default_navigation_menu_tags without applying DiscourseTagging.filter_visible for the anonymous viewer. An unauthenticated user can retrieve restricted tag names and descriptions through /site.json when those tags are limited by inaccessible categories, category tag groups, or tag-group permissions. This issue is fixed in versions 2026.1.6, 2026.5.2, 2026.6.1, and 2026.7.0.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-862\", \"description\": \"CWE-862: Missing Authorization\"}]}], \"providerMetadata\": {\"orgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"shortName\": \"GitHub_M\", \"dateUpdated\": \"2026-08-10T15:56:53.723Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-72723\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-08-10T21:11:02.865Z\", \"dateReserved\": \"2026-08-10T13:48:09.545Z\", \"assignerOrgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"datePublished\": \"2026-08-10T15:56:53.723Z\", \"assignerShortName\": \"GitHub_M\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





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.

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.