CVE-2026-34213

OVERVIEW CVE-2026-34213 is an improper authorization vulnerability affecting Docmost, an open-source collaborative wiki and documentation platform. The flaw exists in versions 0.3.0 through 0.70.x and allows low-privileged authenticated users to overwrite file attachments belonging to other users within the same workspace by manipulating attachment IDs submitted to the file upload endpoint. This is a remote integrity issue that requires no user interaction from victims. SEVERITY The vulnerability carries a CVSS v3.1 score of 5.4 (Medium) with a network-based attack vector that requires only low-level user privileges and no special conditions. While the attack is relatively easy to execute, impact is limited to integrity compromise of attachments and potential availability disruption, with no confidentiality impact. The FAUCET Risk Score of 32.0/100 and minimal EPSS score indicate this poses a manageable but notable threat. EXPLOITATION STATUS There is no evidence of active exploitation in the wild, as the vulnerability is not listed on the Known Exploited Vulnerabilities (KEV) catalog and remains inactive on vulnerability hot lists. No publicly available proof-of-concept code has been identified. The issue was addressed in version 0.71.0, and organizations running Docmost should prioritize updating to this patched version to eliminate the authorization bypass.