CORS misconfiguration in socket.io

MEDIUM 4.3CVE-2020-28481 · GHSA-fxwf-4rqh-v8g3 · Published 19/01/2021 · updated 17/06/2026

In short

CVE-2020-28481 is a MEDIUM (CVSS 4.3) vulnerability affecting socket.io (socket), socket.io.
Chance of exploitation in the next 30 days (EPSS): 0.74%, higher than 54.8% of all vulnerabilities.
Fix: update to 2.4.0 or later.

Package	Affected versions	Patched versions
socket.io socket	`< 2.4.0`	`2.4.0`
socket.io npm	`< 2.4.0`	`2.4.0`

The package socket.io before 2.4.0 are vulnerable to Insecure Defaults due to CORS Misconfiguration. All domains are whitelisted by default.

NVD description

The package socket.io before 2.4.0 are vulnerable to Insecure Defaults due to CORS Misconfiguration. All domains are whitelisted by default.

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