Affected versions of `socket.io` depend on `Math.random()` to create socket IDs, and therefore the IDs are predictable. With enough information on prior IDs, an attacker may be able to guess the socket ID and gain access to socket.io servers without authorization.

## Recommendation

Update to v0.9.7 or later.

Affected Packages

npm socket.io

Affected versions: 0 (fixed in 0.9.7)

Related CVEs

CVE-2017-16031

Key Information

GHSA ID

GHSA-qv2v-m59f-v5fw

Published

November 7, 2018 12:29 AM

Last Modified

September 16, 2021 9:04 PM

CVSS Score

7.5 /10

Primary Ecosystem

npm

Primary Package

socket.io

GitHub Reviewed

✓ Yes

Dataset

Last updated: July 3, 2025 6:26 AM

Data from GitHub Advisory Database. This information is provided for research and educational purposes.