Fluid Attacks Database

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.

Mitigation

Update Impact

Minimal update. May introduce new vulnerabilities or breaking changes.

Ecosystem	Component	Affected version	Patched versions
npm	socket.io-parser	>=0 <3.3.5 \|\| >=3.4.0 <3.4.4 \|\| >=4.0.0 <4.2.6	3.3.5, 3.4.4, 4.2.6
debian 12	node-socket.io-parser	=4.2.1+~3.1.0-2 \|\| =4.2.1+~3.1.0-3 \|\| =4.2.1+~3.1.0-4 \|\| =4.2.4+~3.1.2-1 \|\| =4.2.4+~3.1.2-2	-
debian 13	node-socket.io-parser	=4.2.1+~3.1.0-3 \|\| =4.2.1+~3.1.0-4 \|\| =4.2.4+~3.1.2-1 \|\| =4.2.4+~3.1.2-2	-
debian 14	node-socket.io-parser	=4.2.1+~3.1.0-3 \|\| >=0 <4.2.1+~3.1.0-4	4.2.1+~3.1.0-4

Aliases

1. CVE-2026-331512. NVD-2026-331513. OSV-2026-331514. OSV-DEBIAN-2026-331515. GHSA-677m-j7p3-52f96. GCVE-2026-331517. SECURITY-TRACKER-CVE-2026-33151

References

1. https://github.com/socketio/socket.io/security/advisories/GHSA-677m-j7p3-52f92. https://github.com/socketio/socket.io/commit/719f9ebab0772ffb882bd614b387e585c1aa75d43. https://github.com/socketio/socket.io/commit/9d39f1f080510f036782f2177fac701cc041faaf4. https://github.com/socketio/socket.io/commit/b25738c416c4e32fbff62ee182afa8f6d0dacf78

Does your application use this vulnerable software?

During the free trial, our tools assess your application, identify vulnerabilities, and provide recommendations for their remediation.