CVE-2026-26207

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-26207", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-02-11T19:56:24.814Z", "datePublished": "2026-02-26T15:04:14.557Z", "dateUpdated": "2026-02-26T21:33:42.157Z"}, "containers": {"cna": {"title": "DIscourse's discourse-policy plugin lacks post access check", "problemTypes": [{"descriptions": [{"cweId": "CWE-862", "lang": "en", "description": "CWE-862: Missing Authorization", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.4, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N", "version": "3.1"}}], "references": [{"name": "https://github.com/discourse/discourse/security/advisories/GHSA-jr4h-w6p5-w55r", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/discourse/discourse/security/advisories/GHSA-jr4h-w6p5-w55r"}], "affected": [{"vendor": "discourse", "product": "discourse", "versions": [{"version": "< 2025.12.2", "status": "affected"}, {"version": ">= 2026.1.0-latest, < 2026.1.1", "status": "affected"}, {"version": ">= 2026.2.0-latest, < 2026.2.0", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-02-26T15:04:14.557Z"}, "descriptions": [{"lang": "en", "value": "Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, `discourse-policy` plugin allows any authenticated user to interact with policies on posts they do not have permission to view. The `PolicyController` loads posts by ID without verifying the current user's access, enabling policy group members to accept/unaccept policies on posts in private categories or PMs they cannot see and any authenticated user to enumerate which post IDs have policies attached via differentiated error responses (information disclosure). The issue is patched in versions 2025.12.2, 2026.1.1, and 2026.2.0 by adding a `guardian.can_see?(@post)` check in the `set_post` before_action, ensuring post visibility is verified before any policy action is processed. As a workaround, disabling the discourse-policy plugin (`policy_enabled = false`) eliminates the vulnerability. There is no other workaround without upgrading."}], "source": {"advisory": "GHSA-jr4h-w6p5-w55r", "discovery": "UNKNOWN"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-26207", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-02-26T21:07:32.199815Z"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-02-26T21:33:42.157Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-26207", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-02-26T21:07:32.199815Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-02-26T21:07:33.630Z"}}], "cna": {"title": "DIscourse's discourse-policy plugin lacks post access check", "source": {"advisory": "GHSA-jr4h-w6p5-w55r", "discovery": "UNKNOWN"}, "metrics": [{"cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.4, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "LOW", "confidentialityImpact": "LOW"}}], "affected": [{"vendor": "discourse", "product": "discourse", "versions": [{"status": "affected", "version": "< 2025.12.2"}, {"status": "affected", "version": ">= 2026.1.0-latest, < 2026.1.1"}, {"status": "affected", "version": ">= 2026.2.0-latest, < 2026.2.0"}]}], "references": [{"url": "https://github.com/discourse/discourse/security/advisories/GHSA-jr4h-w6p5-w55r", "name": "https://github.com/discourse/discourse/security/advisories/GHSA-jr4h-w6p5-w55r", "tags": ["x_refsource_CONFIRM"]}], "descriptions": [{"lang": "en", "value": "Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, `discourse-policy` plugin allows any authenticated user to interact with policies on posts they do not have permission to view. The `PolicyController` loads posts by ID without verifying the current user's access, enabling policy group members to accept/unaccept policies on posts in private categories or PMs they cannot see and any authenticated user to enumerate which post IDs have policies attached via differentiated error responses (information disclosure). The issue is patched in versions 2025.12.2, 2026.1.1, and 2026.2.0 by adding a `guardian.can_see?(@post)` check in the `set_post` before_action, ensuring post visibility is verified before any policy action is processed. As a workaround, disabling the discourse-policy plugin (`policy_enabled = false`) eliminates the vulnerability. There is no other workaround without upgrading."}], "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": "2026-02-26T15:04:14.557Z"}}}, "cveMetadata": {"cveId": "CVE-2026-26207", "state": "PUBLISHED", "dateUpdated": "2026-02-26T21:33:42.157Z", "dateReserved": "2026-02-11T19:56:24.814Z", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "datePublished": "2026-02-26T15:04:14.557Z", "assignerShortName": "GitHub_M"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"product": "discourse", "vendor": "discourse", "versions": [{"status": "affected", "version": "< 2025.12.2"}, {"status": "affected", "version": ">= 2026.1.0-latest, < 2026.1.1"}, {"status": "affected", "version": ">= 2026.2.0-latest, < 2026.2.0"}]}], "source": "security-advisories@github.com"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*", "matchCriteriaId": "6DB837D7-28C8-4E0F-B55F-AAAA36F32035", "versionEndExcluding": "2025.12.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*", "matchCriteriaId": "1CAFCC9D-53D7-4017-85A5-EE6CA5A6A11C", "versionEndExcluding": "2026.1.1", "versionStartIncluding": "2026.1.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:discourse:discourse:2026.2.0:*:*:*:latest:*:*:*", "matchCriteriaId": "BB002FDC-BC71-4C46-8AAF-A34EC717E0E7", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, `discourse-policy` plugin allows any authenticated user to interact with policies on posts they do not have permission to view. The `PolicyController` loads posts by ID without verifying the current user's access, enabling policy group members to accept/unaccept policies on posts in private categories or PMs they cannot see and any authenticated user to enumerate which post IDs have policies attached via differentiated error responses (information disclosure). The issue is patched in versions 2025.12.2, 2026.1.1, and 2026.2.0 by adding a `guardian.can_see?(@post)` check in the `set_post` before_action, ensuring post visibility is verified before any policy action is processed. As a workaround, disabling the discourse-policy plugin (`policy_enabled = false`) eliminates the vulnerability. There is no other workaround without upgrading."}, {"lang": "es", "value": "Discourse es una plataforma de discusi\u00f3n de c\u00f3digo abierto. Antes de las versiones 2025.12.2, 2026.1.1 y 2026.2.0, el plugin 'discourse-policy' permite a cualquier usuario autenticado interactuar con pol\u00edticas en publicaciones que no tienen permiso para ver. El 'PolicyController' carga publicaciones por ID sin verificar el acceso del usuario actual, permitiendo a los miembros del grupo de pol\u00edticas aceptar/rechazar pol\u00edticas en publicaciones en categor\u00edas privadas o mensajes privados (PMs) que no pueden ver y a cualquier usuario autenticado enumerar qu\u00e9 IDs de publicaciones tienen pol\u00edticas adjuntas a trav\u00e9s de respuestas de error diferenciadas (revelaci\u00f3n de informaci\u00f3n). El problema se ha parcheado en las versiones 2025.12.2, 2026.1.1 y 2026.2.0 al a\u00f1adir una verificaci\u00f3n 'guardian.can_see?(@post)' en la acci\u00f3n previa 'set_post', asegurando que la visibilidad de la publicaci\u00f3n se verifica antes de que se procese cualquier acci\u00f3n de pol\u00edtica. Como soluci\u00f3n alternativa, deshabilitar el plugin discourse-policy ('policy_enabled = false') elimina la vulnerabilidad. No hay otra soluci\u00f3n alternativa sin actualizar."}], "id": "CVE-2026-26207", "lastModified": "2026-06-17T10:25:56.590", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.4, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 2.5, "source": "security-advisories@github.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-26207", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-02-26T21:07:32.199815Z", "version": "2.0.3"}}]}, "published": "2026-02-26T16:24:07.163", "references": [{"source": "security-advisories@github.com", "tags": ["Vendor Advisory"], "url": "https://github.com/discourse/discourse/security/advisories/GHSA-jr4h-w6p5-w55r"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-862"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,2025.12.2)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[2026.1.0-latest,2026.1.1)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[2026.2.0-latest,2026.2.0)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "discourse", "source": "cna", "vendor": "discourse"}, "product": "discourse", "vendor": "discourse"}], "analysis": {"en": {"generated_at": "2026-04-18T10:23:03.539211+00:00", "value": {"mitigation_remediation": ["Upgrade Discourse to v2025.12.2, v2026.1.1, or v2026.2.0 where the disclosure check has been added", "Disable the discourse-policy plugin by setting policy_enabled=false to eliminate the vulnerability", "Verify that no remnants of old plugin code remain in the deployment and audit policy-related API endpoints for access control checks"], "summary": {"action": "Patch or Disable", "impact": "Unauthorized policy manipulation and information disclosure on private posts"}, "threat_synthesis": {"affected_systems": "Affected systems are installations of the open\u2011source Discourse discussion platform running any version prior to 2025.12.2, 2026.1.1, or 2026.2.0 that have the discourse\u2011policy plugin enabled. The affected vendor and product are Discourse Discussion Platform, specifically the discourse-policy plugin module.", "description_and_impact": "The discourse-policy plugin permitted any authenticated user to load posts by ID and perform policy actions without checking the caller\u2019s visibility rights. This allowed users to accept or unaccept policies on posts in private categories or private messages that they could not normally view, and also enabled enumeration of which post IDs have policies attached through differing error messages. The result was exposure of policy state and the ability to enumerate post IDs with policies attached. Since the flaw centers on lack of authorization, the impact is limited to coordinated enforcement of policies and the leakage of sensitive post identifiers, rather than full code execution or arbitrary data exfiltration.", "risk_and_exploitability": "Risk and exploitability is moderate: the CVSS base score of 5.4 indicates average impact, while the EPSS score of less than 1% suggests a low probability of active exploitation. The vulnerability is not listed in the CISA KEV catalog. Exploitation requires authenticated access to the forum, and an attacker can perform the unauthorized policy actions by simply issuing the normal API calls that the plugin uses. Since the flaw involves a missing access check, an attacker does not need additional privilege escalation beyond a user account."}}}}, "created": "2026-02-27T09:07:27.756123+00:00", "updated": "2026-04-18T10:30:35.762043+00:00", "vendors": ["discourse", "discourse$PRODUCT$discourse"]}