Is CVE-2020-28481 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2020-28481 being exploited in the wild.

How severe is CVE-2020-28481?

Low severity, with a CVSS score of 3.1, published 20 January 2021.

Which products and versions are affected?

socket.io (npm) SEMVER:introduced=0,fixed=2.4.0.

Is there a fix for CVE-2020-28481?

Yes. socket.io (npm): upgrade to 2.4.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2020-28481 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2020-28481?

Check whether you run socket.io (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2020-28481: socket.io CORS misconfiguration

CVE-2020-28481 · Severity: low · CVSS 3.1 · Published 2021-01-20

socket.io is a JavaScript library that enables real-time bidirectional communication between web clients and servers. A CORS (Cross-Origin Resource Sharing) misconfiguration in versions before 2.4.0 whitelists all domains by default, allowing attackers from any domain to make unauthorized requests to applications using vulnerable versions. This can result in API key theft, session hijacking, and unauthorized access to sensitive data.

Technologies: socket.io (npm). Vendors: npm.

Quick answers

Is CVE-2020-28481 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2020-28481 being exploited in the wild.
How severe is CVE-2020-28481?: Low severity, with a CVSS score of 3.1, published 20 January 2021.
Which products and versions are affected?: socket.io (npm) SEMVER:introduced=0,fixed=2.4.0.
Is there a fix for CVE-2020-28481?: Yes. socket.io (npm): upgrade to 2.4.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2020-28481 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2020-28481?: Check whether you run socket.io (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

socket.io (npm): upgrade to 2.4.0 or later
```
npm install socket.io@2.4.0
```

Technical details

The vulnerability is an insecure-defaults CORS misconfiguration (CWE-346, CWE-453) in socket.io before version 2.4.0. The library accepts arbitrary origins in the Access-Control-Allow-Origin header, effectively trusting all domains by default. An attacker can craft a malicious web page that initiates socket.io connections to a vulnerable target application; if a victim visits the attacker's page, the browser will establish the connection and the attacker can send authenticated requests. No user interaction beyond visiting a malicious site is required. The vulnerability was fixed in version 2.4.0 with a commit that restricts CORS origins to proper whitelisting.

Affected products

socket.io socket.io before 2.4.0

Identifiers

CVE-2020-28481
GHSA-fxwf-4rqh-v8g3

Timeline

2020-10-29: disclosed
2021-01-20: advisory
2.4.0: patched

References

https://github.com/socketio/socket.io/issues/3671

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