Improper certificate validation in socketio Socket Firewall
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Spoofing
- Confidentiality · integrity · availability
- Low · High · Low
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-295.
Summary
Socket Firewall (socketdev/socket-registry-firewall) in registry mode before 2.0.0 does not verify upstream TLS certificates by default. When the api_ssl_verify and upstream_ssl_verify configuration keys are omitted from socket.yml, the generated configuration sets SOCKET_API_SSL_VERIFY='false' and UPSTREAM_SSL_VERIFY='false', and the OpenResty/Lua HTTP client used for outbound requests accepts any certificate, including self-signed and otherwise untrusted certificates, without validating the chain. An attacker positioned to intercept traffic between Socket Firewall and the Socket API or an upstream package registry can present a crafted certificate and modify responses in transit, including substituting malicious package content or altering the allow/block decisions the firewall enforces. Setting api_ssl_verify: true and upstream_ssl_verify: true enables verification; however, in versions before 1.1.334, the generated nginx configuration did not emit lua_ssl_trusted_certificate, and thus verification could not be used successfully without manually patching the generated configuration. Version 2.0.0 changes the default for both settings to true.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA Socket Firewall (Socket) Fixed in 2.0.0
Timeline
- 2026-10-02 Threatist record created from CVE-2026-90651
- 2026-10-03 Alias added: GHSA-jrp2-p3px-f5p5
References
More socketio vulnerabilities
- TI-2022-20281 Uncaught exception in engine.io CVSS 3.1HIGH 7.1
- TI-2022-02236 Socket.io - Improper type validation in attachment parsing CVSS 3.1CRITICAL 10.0
- TI-2026-25581 socket.io allows an unbounded number of binary attachments CVSS 4.0HIGH 8.7
- TI-2022-06052 Uncaught Exception in engine.io CVSS 3.1HIGH 7.5
- TI-2023-15971 Insufficient validation when decoding a Socket.IO packet CVSS 3.1HIGH 7.5
- TI-2026-73305 Uncaught exception in Engine.IO lets clients crash Node.js processes CVSS 3.1HIGH 7.5
Sources
- CVE-2026-90651 · CVE Program
- CVE-2026-90651 · NVD
- FIRST EPSS
- GHSA-jrp2-p3px-f5p5 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences