CVE-2020-36049: Resource Exhaustion in socket.io-parser
Summary
CVE-2020-36049: Resource exhaustion in socket.io-parser. Affects socket.io-parser across 2 version ranges.
< 3.3.2
>= 3.4.0, < 3.4.1
Fixed in 3.3.2 or 3.4.1, depending on the release line you run. How to fix ↓
Also tracked for
- node-socket.io-parser · Debian:11
The same CVE-2020-36049 is tracked separately for each ecosystem and vendor. Its fix information is the same; the package and affected versions differ.
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Background
The socket.io-parser npm package is a library used for parsing and serializing socket.io packets. It is commonly used in applications that utilize the socket.io framework for real-time communication between clients and servers. The package provides functions for encoding and decoding packets, allowing for efficient communication over websockets. However, versions before 3.3.2 and 3.4.1 of the package are vulnerable to a resource exhaustion issue.
Vulnerability Detail
The vulnerability in socket.io-parser (CVE-2020-36049) arises from a concatenation approach used in the package. Attackers can exploit this vulnerability by sending a large packet, causing a denial of service (DoS) attack and consuming excessive memory. This can lead to the unavailability of the affected application or server. The vulnerability has a CVSS score of 7.5, indicating a high severity level.
How To Fix
Latest published version: 4.2.7 as of 23 Oct 2026
npm install socket.io-parser@4.2.7Upgrading to it may include breaking changes; the versions below are the minimum fixed release for this vulnerability.
If you can't move to the latest
The minimum fixed version depends on the release line you run.
-
< 3.3.23.3.2npm install socket.io-parser@3.3.2 -
>= 3.4.0, < 3.4.13.4.1npm install socket.io-parser@3.4.1
Tip — Not sure which release line you're on? Vulert can find the fix for the version you are using. Scan free →
Workaround
There is no known workaround for this vulnerability. It is crucial to update the package to the fixed version as soon as possible.
Conclusion
The socket.io-parser npm package before versions 3.3.2 and 3.4.1 is vulnerable to a resource exhaustion issue that can be exploited to cause a denial of service attack. It is crucial to update the package to version 3.3.2 or later to mitigate this vulnerability. For further support on vulnerability remediation, please contact DevNack.com.
See every vulnerability recorded for socket.io-parser →
FAQ
The vulnerability can lead to a denial of service (DoS) attack by consuming excessive memory, resulting in the unavailability of the affected application or server.
You can use the Vulert Playground (https://vulert.com/scanner) to check if your application is affected by this vulnerability. Simply upload your package-lock.json file and it will provide real-time alerts for open-source vulnerabilities.
Yes, the vulnerability can be fixed by updating the socket.io-parser package to version 3.3.2 or later.
There are no known workarounds for this vulnerability. It is recommended to update the package to the fixed version.
The CVSS score of this vulnerability is 7.5, indicating a high severity level.
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