Vulnerability Description
Feathersjs is a framework for creating web APIs and real-time applications with TypeScript or JavaScript. In versions 5.0.39 and below, origin validation uses startsWith() for comparison, allowing attackers to bypass the check by registering a domain that shares a common prefix with an allowed origin.The getAllowedOrigin() function checks if the Referer header starts with any allowed origin, and this comparison is insufficient as it only validates the prefix. This is exploitable when the origins array is configured and an attacker registers a domain starting with an allowed origin string (e.g., https://target.com.attacker.com bypasses https://target.com). On its own, tokens are still redirected to a configured origin. However, in specific scenarios an attacker can initiate the OAuth flow from an unauthorized origin and exfiltrate tokens, achieving full account takeover. This issue has bee fixed in version 5.0.40.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Feathersjs | Feathers | < 5.0.40 |
Related Weaknesses (CWE)
References
- https://github.com/feathersjs/feathers/commit/ee19a0ae9bc2ebf23b1fe598a1f7361981Patch
- https://github.com/feathersjs/feathers/releases/tag/v5.0.40ProductRelease Notes
- https://github.com/feathersjs/feathers/security/advisories/GHSA-mp4x-c34x-wv3xThird Party Advisory
FAQ
What is CVE-2026-27192?
CVE-2026-27192 is a vulnerability with a CVSS score of 8.1 (HIGH). Feathersjs is a framework for creating web APIs and real-time applications with TypeScript or JavaScript. In versions 5.0.39 and below, origin validation uses startsWith() for comparison, allowing att...
How severe is CVE-2026-27192?
CVE-2026-27192 has been rated HIGH with a CVSS base score of 8.1/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-27192?
Check the references section above for vendor advisories and patch information. Affected products include: Feathersjs Feathers.