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{"configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*", "matchCriteriaId": "452E5338-8153-4A3E-B634-CAE43E14B557", "versionEndExcluding": "2025.12.2", "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, TL4 users can publish topics into staff-only categories via the `publish_to_category` topic timer, bypassing authorization checks. Versions 2025.12.2, 2026.1.1, and 2026.2.0 patch the issue. No known workarounds are available."}, {"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, los usuarios TL4 pueden publicar temas en categor\u00edas solo para el personal a trav\u00e9s del temporizador de temas 'publish_to_category', omitiendo las comprobaciones de autorizaci\u00f3n. Las versiones 2025.12.2, 2026.1.1 y 2026.2.0 parchean el problema. No se conocen soluciones alternativas disponibles."}], "id": "CVE-2026-28227", "lastModified": "2026-03-02T18:11:29.687", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 2.7, "baseSeverity": "LOW", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "HIGH", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 1.2, "impactScore": 1.4, "source": "nvd@nist.gov", "type": "Primary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 1.2, "baseSeverity": "LOW", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "UNREPORTED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "HIGH", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "LOW", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-02-26T22:20:49.927", "references": [{"source": "security-advisories@github.com", "tags": ["Vendor Advisory"], "url": "https://github.com/discourse/discourse/security/advisories/GHSA-m49w-78mh-87jp"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-863"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{"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": "2026-04-16T16:01:00.189953+00:00", "value": {"mitigation_remediation": ["Upgrade Discourse to at least version 2025.12.2, 2026.1.1, or 2026.2.0 to apply the vendor patch that restores proper authorization checks for publish_to_category timers.", "Review all existing topic timers that target staff-only categories and either delete or modify them so that they cannot publish to restricted areas.", "Audit staff-only categories for any unauthorized topics that may have been created before the update and remove or flag them as needed."], "summary": {"action": "Patch Now", "impact": "Privilege Escalation"}, "threat_synthesis": {"affected_systems": "Discourse participants running any version prior to 2025.12.2, 2026.1.1, or 2026.2.0 are affected. The issue applies to the Discourse application itself, and the specific CPE strings identify all versions of the software found in the vulnerability list. All other versions released after those patches are considered fixed.", "description_and_impact": "Discourse, an open source discussion platform, contains a flaw that allows any user with Teaching Lead (TL4) authority to create new topics in staff-only categories using the publish_to_category function of a topic timer. The vulnerability stems from missing authorization checks, giving privileged users unauthorized content insertion capability and effectively elevating their privileges within restricted categories. This flaw is classified as CWE\u2011863, indicating a missing authorization check.", "risk_and_exploitability": "With a CVSS score of 1.2, attackers face only minimal consequences, and the EPSS score of less than 1% indicates a low probability of exploitation. No known exploit activity exists, and the vulnerability is not included in the CISA Known Exploited Vulnerabilities catalog. The likely attack vector requires an authenticated TL4 user and does not assume a remote execution method. In absence of a public exploit, the risk is limited to potential misuse by legitimate staff members with TL4 rights who can trigger topic timers to publish content where they should not."}}}}, "created": "2026-02-27T09:04:06.002624+00:00", "updated": "2026-04-16T16:15:08.454373+00:00", "vendors": ["discourse", "discourse$PRODUCT$discourse"]}