{"id":"CVE-2026-77167","title":"Abusing the federated share endpoint, an attacker can write arbitrary rows into the oc_share_external database table","summary":"Abusing the federated share endpoint, an attacker can write arbitrary rows into the oc_share_external database table. These rows persist indefinitely — there is no automatic cleanup mechanism. Three distinct denial-of-service conditions …","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cvssSource":"cna","cwe":["CWE-400"],"vendor":"Nextcloud","product":"server","affected":["server >= 22.0.0 <= 34.0.0"],"published":"2026-10-27","updated":"2026-10-27","sourceUpdated":"2026-10-27T16:15:34.778Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-77167","references":[{"url":"https://hackerone.com/reports/3679640"}],"tags":["cve.org"],"ingestedAt":"2026-10-27T16:32:34.401Z","slug":"CVE-2026-77167","body":"## Overview\n\nAbusing the federated share endpoint, an attacker can write arbitrary rows into the oc_share_external database table. These rows persist indefinitely — there is no automatic cleanup mechanism. Three distinct denial-of-service conditions follow from this write primitive, all triggered from the same unauthenticated source and all self-renewing on a 24-hour cycle for as long as the injected rows remain in the database.\n\n## Affected\n\n- `server >= 22.0.0 <= 34.0.0`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}