CVE-2026-77167 (GCVE-0-2026-77167)

Vulnerability from cvelistv5 – Published: 2026-10-27 16:15 – Updated: 2026-11-04 20:25
VLAI
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 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.
Severity
7.5 (High)
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-04 20:07 UTC
CWE
  • CWE-400 - Uncontrolled Resource Consumption
Assigner
hackerone CNA under the mitre root
CNA scorecard D 59/100 over 213 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Nextcloud server Affected: 22.0.0 , ≤ 34.0.0 (semver)
guessed Create a notification for this product.
Credits
ncsc_nl
Show details on NVD website
To clipboard 

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