CVE-2023-31125: Uncaught exception in engine.io
Impact
A specially crafted HTTP request can trigger an uncaught exception on the Engine.IO server, thus killing the Node.js process.
TypeError: Cannot read properties of undefined (reading 'handlesUpgrades') at Server.onWebSocket (build/server.js:515:67)
This impacts all the users of the engine.io package, including those who uses depending packages like socket.io.
Patches
A fix has been released today (2023/05/02): 6.4.2
This bug was introduced in version 5.1.0 and included in version 4.1.0 of the socket.io parent package. Older versions are not impacted.
For socket.io users:
| Version range | engine.io version | Needs minor update? | |-----------------------------|---------------------|--------------------------------------------------------------------------------------------------------| | socket.io@4.6.x | ~6.4.0 | npm audit fix should be sufficient | | socket.io@4.5.x | ~6.2.0 | Please upgrade to socket.io@4.6.x | | socket.io@4.4.x | ~6.1.0 | Please upgrade to socket.io@4.6.x | | socket.io@4.3.x | ~6.0.0 | Please upgrade to socket.io@4.6.x | | socket.io@4.2.x | ~5.2.0 | Please upgrade to socket.io@4.6.x | | socket.io@4.1.x | ~5.1.1 | Please upgrade to socket.io@4.6.x | | socket.io@4.0.x | ~5.0.0 | Not impacted | | socket.io@3.1.x | ~4.1.0 | Not impacted | | socket.io@3.0.x | ~4.0.0 | Not impacted | | socket.io@2.5.0 | ~3.6.0 | Not impacted | | socket.io@2.4.x and below | ~3.5.0 | Not impacted |
Workarounds
There is no known workaround except upgrading to a safe version.
For more information
If you have any questions or comments about this advisory:
Open an issue in engine.io
Thanks to Thomas Rinsma from Codean for the responsible disclosure.
Other sources
Engine.IO is the implementation of transport-based cross-browser/cross-device bi-directional communication layer for Socket.IO. An uncaught exception vulnerability was introduced in version 5.1.0 and included in version 4.1.0 of the socket.io parent package. Older versions are not impacted. A specially crafted HTTP request can trigger an uncaught exception on the Engine.IO server, thus killing the Node.js process. This impacts all the users of the engine.io package, including those who use depending packages like socket.io. This issue was fixed in version 6.4.2 of Engine.IO. There is no known workaround except upgrading to a safe version.
Engine.IO is vulnerable to a denial of service, caused by an uncaught exception. By sending a specially crafted HTTP request, a remote authenticated attacker could exploit this vulnerability to cause a denial of service.
— IBM
Affected Software
Remediation
Event History
Frequently Asked Questions
What is CVE-2023-31125?
CVE-2023-31125 is a vulnerability in Engine.IO, a transport-based communication layer for Socket.IO, that allows for a denial of service attack caused by an uncaught exception.
How does CVE-2023-31125 affect Socket.IO and Engine.IO?
CVE-2023-31125 affects Socket.IO version 4.1.0 and Engine.IO versions 5.1.0 to 6.4.2, allowing for a denial of service attack.
What versions of Socket.IO and Engine.IO are affected by CVE-2023-31125?
Socket.IO version 4.1.0 and Engine.IO versions 5.1.0 to 6.4.2 are affected by CVE-2023-31125.
What is the severity of CVE-2023-31125?
CVE-2023-31125 has a severity rating of 6.5, which is classified as medium.
How can I mitigate CVE-2023-31125?
To mitigate CVE-2023-31125, it is recommended to upgrade to the latest version of Socket.IO and Engine.IO, which addresses the vulnerability.