Vulnerability · Published Jun 18, 2026 · Assigned by GitHub_M
CVE-2026-49252deepstream is vulnerable to prototype pollution
Critical 9.9
In plain English
A critical-severity prototype pollution in deepstream.io from deepstreamIO. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 41% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | @deepstream/server | 10.0.5 | GHSA-9v98-6g37-x9g6 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| deepstreamIO | deepstream.io | < 10.0.5 |
Weakness: CWE-1321 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:L