CVE-2026-69185: 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
Other sources
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 for a large number of binary attachments and buffer them, which can be exploited to make the server run out of memory. This vulnerability is fixed in 4.2.7, 3.4.5, and 3.3.6.
— MITRE
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
npm/socket.io-parserto a version that resolves this vulnerability.Fixed in 3.3.6 - Upgrade
Upgrade
npm/socket.io-parserto a version that resolves this vulnerability.Fixed in 3.4.5 - Upgrade
Upgrade
npm/socket.io-parserto a version that resolves this vulnerability.Fixed in 4.2.7 - Upgrade
Upgrade
socket.io/socket.ioto a version that resolves this vulnerability.Fixed in 4.2.7 - Upgrade
Upgrade
socket.io/socket.ioto a version that resolves this vulnerability.Fixed in 3.4.5 - Upgrade
Upgrade
socket.io/socket.ioto a version that resolves this vulnerability.Fixed in 3.3.6
Event History
Frequently Asked Questions
What is the severity of CVE-2026-69185?
The severity of CVE-2026-69185 is rated as high with a score of 7.5.
What systems are affected by CVE-2026-69185?
CVE-2026-69185 affects systems using the Socket.IO library due to memory exhaustion vulnerabilities.
How do I mitigate CVE-2026-69185?
Mitigation for CVE-2026-69185 involves updating to the fixed versions of Socket.IO that address the memory exhaustion issue.
What is the impact of CVE-2026-69185?
The impact of CVE-2026-69185 is that a specially crafted Socket.IO packet can lead to server memory exhaustion.
Is there any patch available for CVE-2026-69185?
Yes, CVE-2026-69185 has specific patches available that users can apply by updating Socket.IO to the appropriate fixed version.