What is CVE-2026-27191?

CVE-2026-27191 is a medium-severity vulnerability in Feathersjs Feathers, classified under URL Redirection to Untrusted Site (Open Redirect). CVSS score: 6.1/10. Published 2026-02-21.

How severe is CVE-2026-27191?

Medium severity. CVSS v3 base score is 6.1 out of 10.

Open Redirect in Feathersjs Feathers

CVE-2026-27191

Feathersjs is a framework for creating web APIs and real-time applications with TypeScript or JavaScript. Versions 5.0.39 and below the redirect query parameter is appended to the base origin without validation, allowing attackers to steal…

Vulnerability class: Open Redirect

EPSS: 0.003 (16.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

Affected products

Feathersjs Feathers — versions < 5.0.40

Weakness classification (CWE)

CWE-601 — URL Redirection to Untrusted Site (Open Redirect)

References

security-advisories@github.com (x_refsource_CONFIRM, Third Party Advisory)
security-advisories@github.com (Patch, x_refsource_MISC)
security-advisories@github.com (Product, x_refsource_MISC, Release Notes)

Frequently asked questions

What is CVE-2026-27191?: CVE-2026-27191 is a medium-severity vulnerability in Feathersjs Feathers, classified under URL Redirection to Untrusted Site (Open Redirect). CVSS score: 6.1/10. Published 2026-02-21.
How severe is CVE-2026-27191?: Medium severity. CVSS v3 base score is 6.1 out of 10.