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 If you have any questions or comments about this advisory: - Open a discussion [here](https://github.com/socketio/socket.io/discussions)
describes (1)
Related CVEs.
| ID | severity | exploitable | ||
|---|---|---|---|---|
| CVE-2026-69185US | — | — | ||
Socket.IO enables bidirectional and low-latency communication for every platform. Prior to 4.2.7, 3.4.5, and 3.3.6, a specially crafted Socket.IO packet can make the server wait fo… | ||||
references
External citations — patches, advisories, analysis.
- https://github.com/socketio/socket.ioPACKAGE
- https://github.com/socketio/socket.io/commit/7c6ef571a00656718e9e05e3b948fd1758b2a7b4WEB
- https://github.com/socketio/socket.io/commit/9c6323e5cde41bd75df3379b5fc9293664a5f240WEB
- https://github.com/socketio/socket.io/commit/ced94ffa3ac020a8f3c14eb98a3bf34acb14d291WEB
- https://github.com/socketio/socket.io/security/advisories/GHSA-2m8v-j782-fhvrWEB
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