CVE-2026-63116
Received Received - Intake

Permission Bypass in Deepstream Server

Publication date: 2026-09-21

Last updated on: 2026-09-21

Assigner: GitHub, Inc.

Description
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.

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Meta Information

Published
2026-09-21
Last Modified
2026-09-21
Generated
2026-09-21
AI Q&A
2026-09-21
EPSS Evaluated
N/A
NVD
CVE-2026-63116
EUVD
EUVD-2026-84001

Affected Vendors & Products

Showing 4 associated CPEs
Vendor Product Version / Range
deepstreamio deepstream to 10.1.1 (exc)
deepstreamio deepstream 10.1.1
deepstream deepstream to 10.1.1 (exc)
deepstream deepstream 10.1.1

Helpful Resources

Exploitability

CWE
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KEV
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CWE ID Description
CWE-862 The product does not perform an authorization check when an actor attempts to access a resource or perform an action.

Attack-Flow Graph

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Executive Summary

CVE-2026-63116 is a vulnerability in the deepstream.io server affecting versions 10.1.0 and earlier. The issue involves the PATCH_MULTI record action, which is not registered in the Valve permission system's RULES_MAP. This allows unauthorized record writes because the system bypasses permission rules for PATCH_MULTI operations, treating them as unconditionally allowed.

Detection Guidance

To detect this vulnerability, check if your deepstream.io server version is between 10.1.0 and earlier. Verify if the Valve permission system is enabled and if PATCH_MULTI actions are allowed without proper permission checks. Monitor for unauthorized record modifications or unexpected write operations.

Impact Analysis

Any authenticated user can modify arbitrary protected records, corrupt application state, or cause service disruption. Attackers could overwrite admin-only records or perform unauthorized multi-record updates, leading to data corruption or outages. Only deployments using the Valve (ConfigPermission) system are affected; default OpenPermission systems are not impacted.

Compliance Impact

This vulnerability could lead to unauthorized data modifications, violating integrity and access control requirements in GDPR and HIPAA. Unauthorized record changes may result in non-compliance with data protection and security standards, potentially leading to legal and regulatory penalties.

Mitigation Strategies

Upgrade to deepstream.io version 10.1.1 or later to apply the fix. If upgrading is not immediately possible, restrict access to authenticated users and disable the Valve permission system if not required. Review and audit record modification logs for suspicious activity.

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