Auth bypass in Supabase Realtime

CVE-2026-62247

Supabase Realtime provides Broadcast, Presence, and Postgres Changes via WebSockets. Prior to 2.111.2, Realtime authorization does not correctly honor the per-extension presence.read row-level security policy when a private-channel client is allowed presence.write but explicitly denied presence.read. Under that differential policy, the client can receive presence_diff messages containing other members' presence metadata, including application-defined location, online-status, roster, viewing, or typing information. Deployments with uniform presence visibility have no differential, and postgres_changes row data is unaffected. This issue is fixed in version 2.111.2.

Vulnerability class: Broken Access Control

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-62247?
CVE-2026-62247 is a medium-severity vulnerability in Supabase Realtime, classified under Incorrect Authorization. CVSS score: 6.5/10. Published 2026-09-21.
How severe is CVE-2026-62247?
Medium severity. CVSS v3 base score is 6.5 out of 10.