CVE-2026-33395

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{}

{"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": "2026-03-24T21:57:39.579992+00:00", "value": {"mitigation_remediation": ["Update Discourse version 2026.3.0-latest.1, 2026.2.1, or 2026.1.2 to apply the patch", "If upgrading is not immediately possible, disable the discourse-graphviz plugin", "Enable a content security policy to block execution of inline JavaScript"], "summary": {"action": "Apply Patch", "impact": "Stored Cross- Site Scripting"}, "threat_synthesis": {"affected_systems": "Affected installations are those running Discourse with the discourse-graphviz plugin on versions prior to 2026.3.0-latest.1, 2026.2.1, or 2026.1.2. All recent releases include a patch that removes the vulnerability. The product is the open-source Discourse discussion platform.", "description_and_impact": "This vulnerability arises from the discourse-graphviz plugin, which allows authenticated users to embed malicious JavaScript in DOT graph definitions that are stored and rendered as SVG. Once an attacker creates a graph containing a javascript: link, the script executes in the browser context of any user who views the graph, enabling theft of session cookies, arbitrary actions, or credential compromise. The weakness maps to CWE-79\u2014stored cross-site scripting.", "risk_and_exploitability": "The CVSS base score of 4.4 indicates medium risk, while an EPSS score of less than 1\u202f% suggests a low probability of exploitation. The flaw is not listed in the CISA KEV catalog, and exploitation requires a logged-in user to create or modify a graph; additionally, it only manifests when the site\u2019s content security policy is disabled. Thus the threat is moderate but limited by the need for authenticated access and an insecure configuration."}}}}, "created": "2026-03-20T08:54:44.595148+00:00", "updated": "2026-03-25T11:54:25.329906+00:00", "vendors": ["discourse", "discourse$PRODUCT$discourse"]}