CVE-2026-59725
Last modified
CVE-2026-59725 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. Socket.IO enables bidirectional and low-latency communication for every platform. From 4.1.0 before 6.6.7, Engine.IO protocol v4 polling transport does not properly close the HTTP response for invalid binary POST requests with Content-Type: application/octet-stream, allowing an unauthenticated attacker to exhaust server-side connections and sockets. EPSS estimates a 0.35% chance of exploitation in the next 30 days.
Description
Socket.IO enables bidirectional and low-latency communication for every platform. From 4.1.0 before 6.6.7, Engine.IO protocol v4 polling transport does not properly close the HTTP response for invalid binary POST requests with Content-Type: application/octet-stream, allowing an unauthenticated attacker to exhaust server-side connections and sockets. This issue is fixed in version 6.6.7.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Socket | Engine.Io | >= 4.1.0, < 6.6.7 |
References
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
What is CVE-2026-59725?
How severe is CVE-2026-59725?
How do I fix CVE-2026-59725?
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2026
- CVE-2026-59717Home Assistant is open source home automation software focus…4.3
- CVE-2026-5972A vulnerability has been found in FoundationAgents MetaGPT u…9.8
- CVE-2026-59720Hoppscotch is an open source API development ecosystem. Prio…7.5
- CVE-2026-59721Hoppscotch is an open source API development ecosystem. Prio…7.2
- CVE-2026-59723Cline is an autonomous coding agent as an SDK, IDE extension…8.8
- CVE-2026-59724Socket.IO enables bidirectional and low-latency communicatio…7.5
- CVE-2026-59726Ruflo is an agent meta-harness for Claude Code and Codex. Pr…10
- CVE-2026-59727Astro is a web framework for content-driven websites. In ver…2.1
- CVE-2026-59728Astro is a web framework for content-driven websites. In ver…4.3
- CVE-2026-59729Astro is a web framework for content-driven websites. Versio…5.1
- CVE-2026-5973A vulnerability was found in FoundationAgents MetaGPT up to …9.8
- CVE-2026-59730Astro is a web framework for content-driven websites. In ver…2.1
Are you affected by CVE-2026-59725?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST