CVSS 4.0
8.7 highCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:NCVE-2026-33151
Socket.IO is an open source, real-time, bidirectional, event-based, communication framework. Prior to versions 3.3.5, 3.4.4, and 4.2.6, 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. This issue has been patched in versions 3.3.5, 3.4.4, and 4.2.6.
Severity
CVSS 3.1
7.5 highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- EPSS
- 0.5% chance of exploitation in the next 30 days; higher than 44% of CVEs (scores of 2026-10-31)
- CWEs
- CWE-20, CWE-754
- Published
- Modified
- Record from
- the NVD, synced
Affected
- socket:socket.io-parser
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-677m-j7p3-52f9 | npm | socket.io-parser | <3.3.5 | 3.3.5 |
| GHSA-677m-j7p3-52f9 | npm | socket.io-parser | >=3.4.0 <3.4.4 | 3.4.4 |
| GHSA-677m-j7p3-52f9 | npm | socket.io-parser | >=4.0.0 <4.2.6 | 4.2.6 |
References
- https://github.com/socketio/socket.io/commit/719f9ebab0772ffb882bd614b387e585c1aa75d4
- https://github.com/socketio/socket.io/commit/9d39f1f080510f036782f2177fac701cc041faaf
- https://github.com/socketio/socket.io/commit/b25738c416c4e32fbff62ee182afa8f6d0dacf78
- https://github.com/socketio/socket.io/security/advisories/GHSA-677m-j7p3-52f9