Auth bypass in Deepstreamio Deepstream.io

CVE-2026-63116

deepstream is a server that allows clients and backend services to sync data, send messages and make rpcs at scale. From 10.1.0 until 10.1.1, src/services/permission/valve/rules-map.ts omits RECORD_ACTION.PATCH_MULTI from RULES_MAP. When an authenticated user sends a PATCH_MULTI record operation while permission.type is config, getRulesForMessage returns a null rule specification and ConfigPermission.canPerformAction treats the missing specification as an unconditional allow instead of applying RULE_TYPES.WRITE. Any authenticated user can therefore modify arbitrary protected records, corrupt application state, or cause service disruption; deployments using the default permission type none already allow all operations and are not additionally affected. This issue is fixed in version 10.1.1.

Vulnerability class: Broken Access Control

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-63116?
CVE-2026-63116 is a high-severity vulnerability in Deepstreamio Deepstream.io, classified under Missing Authorization. CVSS score: 8.8/10. Published 2026-09-21.
How severe is CVE-2026-63116?
High severity. CVSS v3 base score is 8.8 out of 10.