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Uncaught Exception in engine.io

High severity GitHub Reviewed Published Jan 12, 2022 in socketio/engine.io • Updated Jun 27, 2023

Package

npm engine.io (npm)

Affected versions

>= 4.0.0, < 4.1.2
>= 5.0.0, < 5.2.1
>= 6.0.0, < 6.1.1

Patched versions

4.1.2
5.2.1
6.1.1

Description

Impact

A specially crafted HTTP request can trigger an uncaught exception on the Engine.IO server, thus killing the Node.js process.

RangeError: Invalid WebSocket frame: RSV2 and RSV3 must be clear
at Receiver.getInfo (/.../node_modules/ws/lib/receiver.js:176:14)
at Receiver.startLoop (/.../node_modules/ws/lib/receiver.js:136:22)
at Receiver._write (/.../node_modules/ws/lib/receiver.js:83:10)
at writeOrBuffer (internal/streams/writable.js:358:12)

This impacts all the users of the engine.io package starting from version 4.0.0, including those who uses depending packages like socket.io.

Patches

A fix has been released for each major branch:

Version range Fixed version
engine.io@4.x.x 4.1.2
engine.io@5.x.x 5.2.1
engine.io@6.x.x 6.1.1

Previous versions (< 4.0.0) are not impacted.

For socket.io users:

Version range engine.io version Needs minor update?
socket.io@4.4.x ~6.1.0 -
socket.io@4.3.x ~6.0.0 Please upgrade to socket.io@4.4.x
socket.io@4.2.x ~5.2.0 -
socket.io@4.1.x ~5.1.1 Please upgrade to socket.io@4.4.x
socket.io@4.0.x ~5.0.0 Please upgrade to socket.io@4.4.x
socket.io@3.1.x ~4.1.0 -
socket.io@3.0.x ~4.0.0 Please upgrade to socket.io@3.1.x or socket.io@4.4.x (see here)

In most cases, running npm audit fix should be sufficient. You can also use npm update engine.io --depth=9999.

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:

Thanks to Marcus Wejderot from Mevisio for the responsible disclosure.

References

@darrachequesne darrachequesne published to socketio/engine.io Jan 12, 2022
Published by the National Vulnerability Database Jan 12, 2022
Reviewed Jan 12, 2022
Published to the GitHub Advisory Database Jan 13, 2022
Last updated Jun 27, 2023

Severity

High

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS score

0.398%
(74th percentile)

CVE ID

CVE-2022-21676

GHSA ID

GHSA-273r-mgr4-v34f

Source code

Credits

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