CVE-2026-33151: CWE-20: Improper Input Validation in socketio socket.io
Socket.IO versions prior to 3.3.5, 3.4.4, and 4.2.6 contain an improper input validation vulnerability. A specially crafted packet can cause the server to buffer a large number of binary attachments, potentially exhausting server memory. This vulnerability has been patched in the specified versions.
AI Analysis
Technical Summary
CVE-2026-33151 is an improper input validation vulnerability (CWE-20) in the Socket.IO framework. Before versions 3.3.5, 3.4.4, and 4.2.6, an attacker can send a specially crafted Socket.IO packet that causes the server to wait for and buffer an excessive number of binary attachments. This can lead to memory exhaustion on the server, resulting in denial of service. The issue has been addressed by patches in the mentioned versions.
Potential Impact
Exploitation of this vulnerability can cause the Socket.IO server to run out of memory, leading to denial of service conditions. There is no indication of privilege escalation, code execution, or data disclosure. The CVSS 4.0 base score is 8.7 (high severity), reflecting the potential for disruption of service without requiring authentication or user interaction.
Mitigation Recommendations
Upgrade Socket.IO to version 3.3.5, 3.4.4, or 4.2.6 or later, where this vulnerability is patched. No other mitigation or temporary workaround is indicated by the vendor advisory.
CVE-2026-33151: CWE-20: Improper Input Validation in socketio socket.io
Description
Socket.IO versions prior to 3.3.5, 3.4.4, and 4.2.6 contain an improper input validation vulnerability. A specially crafted packet can cause the server to buffer a large number of binary attachments, potentially exhausting server memory. This vulnerability has been patched in the specified versions.
CVSS v4.0
Score 8.7high
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-33151 is an improper input validation vulnerability (CWE-20) in the Socket.IO framework. Before versions 3.3.5, 3.4.4, and 4.2.6, an attacker can send a specially crafted Socket.IO packet that causes the server to wait for and buffer an excessive number of binary attachments. This can lead to memory exhaustion on the server, resulting in denial of service. The issue has been addressed by patches in the mentioned versions.
Potential Impact
Exploitation of this vulnerability can cause the Socket.IO server to run out of memory, leading to denial of service conditions. There is no indication of privilege escalation, code execution, or data disclosure. The CVSS 4.0 base score is 8.7 (high severity), reflecting the potential for disruption of service without requiring authentication or user interaction.
Mitigation Recommendations
Upgrade Socket.IO to version 3.3.5, 3.4.4, or 4.2.6 or later, where this vulnerability is patched. No other mitigation or temporary workaround is indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-03-17T21:17:08.885Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 69bdacf5e32a4fbe5fcbbe16
Added to database: 03/20/2026, 20:24:21 UTC
Last enriched: 07/11/2026, 10:13:25 UTC
Last updated: 08/01/2026, 10:00:41 UTC
Views: 193
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