Security Policy

March 18, 2026 ยท View on GitHub

Supported Versions

VersionSupported
4.x:white_check_mark:
3.x:white_check_mark:
2.4.x:white_check_mark:
< 2.4.0:x:

Reporting a Vulnerability

To report a security vulnerability in this package, please send an email to @darrachequesne (see address in profile) describing the vulnerability and how to reproduce it.

We will get back to you as soon as possible and publish a fix if necessary.

:warning: IMPORTANT :warning: please do not create an issue in this repository, as attackers might take advantage of it. Thank you in advance for your responsible disclosure.

History

For the socket.io package

DateDescriptionCVE numberAffected versionsPatched versions
July 2012Insecure randomnessCVE-2017-16031<= 0.9.60.9.7
January 2021CORS misconfigurationCVE-2020-28481< 2.4.02.4.0
June 2024Unhandled 'error' eventCVE-2024-38355< 2.5.1
>= 3.0.0, < 4.6.2
2.5.1
4.6.2

From the transitive dependencies:

DateDependencyDescriptionCVE number
January 2016wsBuffer vulnerabilityCVE-2016-10518
January 2016wsDoS due to excessively large websocket messageCVE-2016-10542
November 2017wsDoS in the Sec-Websocket-Extensions header parser-
February 2020engine.ioResource exhaustionCVE-2020-36048
January 2021socket.io-parserResource exhaustionCVE-2020-36049
May 2021wsReDoS in Sec-Websocket-Protocol headerCVE-2021-32640
January 2022engine.ioUncaught exceptionCVE-2022-21676
October 2022socket.io-parserInsufficient validation when decoding a Socket.IO packetCVE-2022-2421
November 2022engine.ioUncaught exceptionCVE-2022-41940
May 2023engine.ioUncaught exceptionCVE-2023-31125
May 2023socket.io-parserInsufficient validation when decoding a Socket.IO packetCVE-2023-32695
June 2024wsDoS when handling a request with many HTTP headersCVE-2024-37890
March 2026socket.io-parserUnbounded number of binary attachmentsCVE-2026-33151

For the socket.io-client package

From the transitive dependencies:

DateDependencyDescriptionCVE number
January 2016wsBuffer vulnerabilityCVE-2016-10518
January 2016wsDoS due to excessively large websocket messageCVE-2016-10542
October 2016engine.io-clientInsecure Defaults Allow MITM Over TLSCVE-2016-10536
November 2017wsDoS in the Sec-Websocket-Extensions header parser-
January 2021socket.io-parserResource exhaustionCVE-2020-36049
May 2021wsReDoS in Sec-Websocket-Protocol headerCVE-2021-32640
October 2022socket.io-parserInsufficient validation when decoding a Socket.IO packetCVE-2022-2421
May 2023socket.io-parserInsufficient validation when decoding a Socket.IO packetCVE-2023-32695
June 2024wsDoS when handling a request with many HTTP headersCVE-2024-37890
March 2026socket.io-parserUnbounded number of binary attachmentsCVE-2026-33151