Socket.IO: Zero-attachment Memory Exhaustion
Impact
A specially crafted Socket.IO packet can make the server wait for a large number of binary attachments and buffer them, which can be exploited to make the server run out of memory.
Patches
| Version range | Used by | Fixed version |
|---|---|---|
>=4.0.0 <4.2.7 |
socket.io@4.x and socket.io-client@4.x |
4.2.7 |
>=3.4.0 <3.4.5 |
socket.io@2.x |
3.4.5 |
<3.3.6 |
socket.io-client@2.x |
3.3.6 |
Workarounds
There is no known workaround except upgrading to a safe version.
For more information
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Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| npm package | socket.io-parser | >= 4.0.0, < 4.2.7, >= 3.4.0, < 3.4.5, < 3.3.6 | 4.2.7, 3.4.5, 3.3.6 |
References
- https://github.com/socketio/socket.io/security/advisories/GHSA-2m8v-j782-fhvr
- https://github.com/socketio/socket.io/commit/7c6ef571a00656718e9e05e3b948fd1758b2a7b4
- https://github.com/socketio/socket.io/commit/9c6323e5cde41bd75df3379b5fc9293664a5f240
- https://github.com/socketio/socket.io/commit/ced94ffa3ac020a8f3c14eb98a3bf34acb14d291
- https://github.com/socketio/socket.io
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- Weakness (CWE)
CWE-20, CWE-754- Platform
- npm
- Package
socket.io-parser- Disclosed
- 03.08.2026
- Updated
- 11.10.2026 10:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-2m8v-j782-fhvr - CC BY 4.0
Vulnerability history: socket.io-parser
All published vulnerabilities of this package (npm package), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 5
- First → latest
- 06.2021 08.2026
- Without a fix
- 0
- Exploited in attacks
- 0
Severity breakdown
- Critical 1
- High 3
- Medium 1
Disclosures per year
- 2021: 1
- 2022: 1
- 2023: 1
- 2024: 0
- 2025: 0
- 2026: 2
-
Socket.IO: Zero-attachment Memory Exhaustion this entry
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