CVE-2026-27191: feathersjs feathers · Open Redirect
Affects feathersjs feathersSource CVE Database V5
Not known to be exploited · CVSS 7.4 High : upgrade to 5.0.40 soon.
Data as of 29 Oct 2026, 19:04 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 21% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.0.40
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 21 Feb 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Upgrade feathersjs feathers to 5.0.40.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| feathersjsfeathers | Affected
| Fixed in
|
AI-suggested
Organizations should immediately upgrade all instances of feathersjs to version 5.0.40 or later, where this vulnerability is fixed. In addition to upgrading, developers should implement strict validation and sanitization of all redirect parameters, ensuring that user-supplied input cannot alter the URL authority or host component. Employing allowlists for redirect destinations and enforcing trailing slashes in origin configurations can prevent exploitation. Security teams should audit existing applications for usage of vulnerable versions and monitor logs for suspicious redirect patterns or unusual access token exposures. Implementing short-lived tokens and binding tokens to specific origins or client contexts can reduce the impact of token theft. User education on avoiding clicking suspicious links and deploying web application firewalls (WAFs) with rules to detect open redirect attempts can provide additional defense layers.
Description
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 access tokens via URL authority injection. This leads to full account takeover, as the attacker obtains the victim's access token and can impersonate them. The application constructs the final redirect URL by concatenating the base origin with the user-supplied redirect parameter. This is exploitable when the origins array is configured and origin values do not end with /. An attacker can supply @attacker.com as the redirect value results in https://target.com@attacker.com#access_token=..., where the browser interprets attacker.com as the host, leading to full account takeover. This issue has been fixed in version 5.0.40.