Vulnerability · Published Nov 4, 2026 · Assigned by GitHub_M
CVE-2026-63183OmniAuth: Host Header Injection Vulnerability
Medium 6.9
In plain English
A medium-severity security flaw in omniauth from omniauth. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 8% of all known vulnerabilities).
Official description
OmniAuth is a flexible authentication system utilizing Rack middleware. Prior to 2.2.0, OmniAuth derives provider callback URLs from request-controlled host information when neither a fixed full_host nor framework-level incoming host validation is configured. A remote unauthenticated client can supply a forged Host header, creating a host header injection risk in applications whose web framework does not verify incoming host headers. Applications using appropriately configured Rails host authorization or a fixed full_host are not affected by this path. This issue is fixed in version 2.2.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | ruby-omniauth | no fix listed | DEBIAN-CVE-2026-63183 |
| Debian:13 | ruby-omniauth | no fix listed | DEBIAN-CVE-2026-63183 |
| Debian:14 | ruby-omniauth | no fix listed | DEBIAN-CVE-2026-63183 |
| Ubuntu:22.04:LTS | ruby-omniauth | no fix listed | UBUNTU-CVE-2026-63183 |
| Ubuntu:24.04:LTS | ruby-omniauth | no fix listed | UBUNTU-CVE-2026-63183 |
| Ubuntu:26.04:LTS | ruby-omniauth | no fix listed | UBUNTU-CVE-2026-63183 |
| Ubuntu:26.10 | ruby-omniauth | no fix listed | UBUNTU-CVE-2026-63183 |
Affected products (as reported)
Weakness: CWE-346 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:L/SA:N