GitHub Advisoryadvisory · Go

GHSA-2gw9-c2r2-f5qf Neko has a Self-service Privilege Escalation for Authenticated Users

HIGH Published 2026-04-21 Modified 2026-06-09 Official page ↗
Aliases
CVE-2026-39386
Ecosystem
Go
Packages
github.com/m1k1o/neko/server
Severity
High
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weaknesses
CWE-20, CWE-269, CWE-284, CWE-639, CWE-862
Reviewed
2026-04-21

Affected packages

• Go github.com/m1k1o/neko/server: >= 3.0.0, < 3.0.11 → fixed in 3.0.11 • Go github.com/m1k1o/neko/server: >= 0.0.0-20250322225643-212bf8a60756, < 0.0.0-20260406184107-c54bcf1ee211 → fixed in 0.0.0-20260406184107-c54bcf1ee211

Description

Impact Any authenticated user can immediately obtain full administrative control of the entire Neko instance (member management, room settings, broadcast control, session termination, etc.). This results in a complete compromise of the instance. Patches The vulnerability has been patched in the following releases: • v3.0.11 (backport release) • v3.1.2 (latest stable release) Users should upgrade to v3.0.11 or later (for the 3.0 branch) or v3.1.2 or later. Workarounds If upgrading is not immediately possible, the following mitigations can reduce risk: • Restrict access to trusted users only (avoid granting accounts to untrusted parties) • Run the instance only when needed; avoid leaving it continuously exposed • Disable or restrict access to the `/api/profile` endpoint if feasible • Monitor for suspicious privilege changes or unexpected administrative actions Note: These are temporary mitigations and do not fully eliminate the vulnerability. Upgrading is strongly recommended. Credits Neko thanks @blitzkrieg-patch for responsibly disclosing this vulnerability and reaching out directly. This contribution helped strengthen the project, and the whole community benefits from it.

Related

Alias · CVE (1)

  • CVE-2026-39386 Neko is a a self-hosted virtual browser that runs in Docker and uses WebRTC In versions 3.0.0 through 3.0.10 and 3.1.0 through 3.1.1, any… vulnerability

Weakness · CWE (5)

  • CWE-20 Improper Input Validation weakness
  • CWE-269 Improper Privilege Management weakness
  • CWE-284 Improper Access Control weakness
  • CWE-639 Authorization Bypass Through User-Controlled Key weakness
  • CWE-862 Missing Authorization weakness

References