CWE-1321Weakness · CWE-1321

CVE-2026-49252

CRITICAL · 9.9 CVSS v3.1 Published 2026-06-18
Patch available
A vendor patch is available. No clean upgrade release — apply the published patch.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable Zero-click Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
deepstream is a server that allows clients and backend services to sync data, send messages and make rpcs at scale. Versions prior to 10.0.5 are vulnerable to Prototype Pollution. Exploitation can lead to potential privilege escalation from any authenticated user with write permission to any record. This issue has been fixed in version 10.0.5.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

deepstream versions prior to 10.0.5 contain a Prototype Pollution vulnerability that allows any authenticated user with write permission to manipulate JavaScript object prototypes, potentially leading to privilege escalation across records.

MitigationUpgrade deepstream to version 10.0.5 or later to patch the Prototype Pollution vulnerability. Verify upgrade in staging before production deployment.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
Low

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Confirm deepstream is present in your environment
    Check for running deepstream processes or installed packages (e.g., look for deepstream in process list, package.json dependencies, or node_modules)
    Affected if deepstream software is found running or installed
  2. Identify the installed deepstream version
    Run the deepstream version command, check package.json/package-lock.json version field, or query the running instance's /info endpoint if exposed
    Affected if the version is lower than 10.0.5 (e.g., 10.0.4, 10.0.0, 9.x.x, etc.)
  3. Verify if authentication is enabled
    Inspect deepstream configuration files (typically conf/config.yml or similar) for auth settings under the auth section
    Affected if authentication is configured and users can log in
  4. Check if write permissions are granted to authenticated users
    Review permission definitions in your permission file (often permissions.yml or permission rules in config) for write access on records
    Affected if any authenticated user role or user has write permission (write: true) on records or wildcards like 'record/*'

You are affected if deepstream is running with a version below 10.0.5 AND authentication is enabled AND write permissions are granted to at least one authenticated user role on records.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Patch available Apply the vendor patch
Vendor patch github.com →
Interim mitigation

Upgrade deepstream to version 10.0.5 or later to patch the Prototype Pollution vulnerability. Verify upgrade in staging before production deployment.

Recommended fix High confidence

10.0.5

  1. Identify the current deepstream server version in use (check package.json, Dockerfile, or running service)
  2. Stop the deepstream service
  3. Update deepstream dependency to version 10.0.5 (e.g., npm install [email protected] or equivalent for your package manager)
  4. Verify the new version is installed correctly
  5. Restart the deepstream service
  6. Confirm the service is running without errors
  7. Test that authenticated users can still access records normally

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed Scoped from the published advisory
  • Consultation3.0 h
  • Implementation2.0 h
  • Testing6.0 h
  • Review / QA2.0 h
13.0 hours of engineering $2,220
Get the patch applied

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,552.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-49252 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-49252 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data