Unprotected Transport of Credentials Affecting oauth2 package, versions >=0.4.0, <2.0.22
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-RUBY-OAUTH2-17275796
- published10 Jun 2026
- disclosed6 Jun 2026
- credittonghuaroot
Introduced: 6 Jun 2026
CVE-2026-54603 (opens in a new tab)How to fix?
Upgrade oauth2 to version 2.0.22 or higher.
Overview
Affected versions of this package are vulnerable to Unprotected Transport of Credentials in the request() function in client.rb, which exposes the Authorization: Bearer value. An attacker in control of a malicious endpoint that is the target of redirects can supply a Location header in a redirect response that uses a protocol-relative URI (starting with //), to obtain the authorization token when a user sends a request. This is caused by an unprotected URI#merge() operation.