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{"configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*", "matchCriteriaId": "4BE96625-3609-410C-B41E-4A824C1A57C0", "versionEndExcluding": "2026.1.2", "versionStartIncluding": "2026.1.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:*", "matchCriteriaId": "FD31CF04-CF2F-4FB9-8880-9243BC7671A7", "versionEndExcluding": "2026.2.1", "versionStartIncluding": "2026.2.0", "vulnerable": true}, {"criteria": "cpe:2.3:a:discourse:discourse:2026.3.0:*:*:*:latest:*:*:*", "matchCriteriaId": "E3FE9277-4F6B-4FD0-991F-F0FB8D226E1C", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Discourse is an open-source discussion platform. Versions prior to 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 have a lack of visibility checks with a user action API endpoint that results in disclosure of the title and post excerpt to unauthorized users, leading to information disclosure. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. No known workarounds are available."}, {"lang": "es", "value": "Discourse es una plataforma de discusi\u00f3n de c\u00f3digo abierto. Las versiones anteriores a 2026.3.0-latest.1, 2026.2.1 y 2026.1.2 carecen de comprobaciones de visibilidad con un endpoint de API de acci\u00f3n de usuario que resulta en la revelaci\u00f3n del t\u00edtulo y el extracto de la publicaci\u00f3n a usuarios no autorizados, lo que lleva a la revelaci\u00f3n de informaci\u00f3n. Las versiones 2026.3.0-latest.1, 2026.2.1 y 2026.1.2 contienen un parche. No se conocen soluciones alternativas disponibles."}], "id": "CVE-2026-27934", "lastModified": "2026-03-25T21:04:13.697", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "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": 8.7, "baseSeverity": "HIGH", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "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": "NONE", "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:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/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": "HIGH", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-03-19T22:16:30.833", "references": [{"source": "security-advisories@github.com", "tags": ["Vendor Advisory"], "url": "https://github.com/discourse/discourse/security/advisories/GHSA-824f-66wh-xx3g"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-201"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[2026.1.0-latest,2026.1.2)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[2026.2.0-latest,2026.2.1)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "2026.3.0-latest"}}], "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": "2026-03-25T23:24:23.030175+00:00", "value": {"mitigation_remediation": ["Upgrade Discourse to a patched version (2026.3.0-latest.1, 2026.2.1, or 2026.1.2).", "Verify that private topic titles are not exposed through the user-action API endpoint.", "Monitor API usage for abnormal requests to private topics and apply rate limiting if needed.", "Stay informed of future advisories by subscribing to Discourse security updates."], "summary": {"action": "Immediate Patch", "impact": "Information Disclosure"}, "threat_synthesis": {"affected_systems": "The vulnerability affects all Discourse releases older than 2026.3.0-latest.1, 2026.2.1, and 2026.1.2. Administrators running those versions are at risk of leaking private topic data. The CPE list confirms that the issue exists in the core product across all platform flavors until the mentioned patches.", "description_and_impact": "Discourse is an open-source discussion platform that inadvertently exposed the title and post excerpt of private topics through its user-action API endpoint. The flaw occurs because the API does not enforce visibility checks, so any user can retrieve that sensitive data. The result is an information disclosure that could surface private discussion details to unauthorized parties. This weakness aligns with CWE-201, an information exposure vulnerability.", "risk_and_exploitability": "The security score is 8.7, indicating a high severity. The EPSS probability is less than 1\u202f%, suggesting that few public exploits are known at present. The vulnerability is not listed in the CISA KEV catalog. The likely attack path is an unauthenticated or insufficiently privileged user sending a crafted request to the user-action API endpoint, which then returns the title and excerpt of a private topic. No public exploit code is publicly documented, but the flaw\u2019s simplicity means it could be abused by a determined adversary through normal API usage."}}}}, "created": "2026-03-20T08:55:49.863877+00:00", "updated": "2026-03-26T12:20:45.135831+00:00", "vendors": ["discourse", "discourse$PRODUCT$discourse"]}