CVE-2026-33151
socket.io allows an unbounded number of binary attachments
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Description
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.
Affected
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
- https://github.com/socketio/socket.io/security/advisories/GHSA-677m-j7p3-52f9
- https://github.com/socketio/socket.io/commit/719f9ebab0772ffb882bd614b387e585c1aa75d4
- https://github.com/socketio/socket.io/commit/9d39f1f080510f036782f2177fac701cc041faaf
- https://github.com/socketio/socket.io/commit/b25738c416c4e32fbff62ee182afa8f6d0dacf78
References (4)
SSVC — Action Prioritization
SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.
CVSS
- Attack Vector
- NETWORK
- Complexity
- LOW
- Privileges
- NONE
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality
- NONE
- Integrity
- NONE
- Availability
- HIGH
Quick Info
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