High 8.6Published Jul 28, 2026

CVE-2026-54603OAuth2::Client#request: Protocol-relative redirect Location overrides authority, leaking bearer Authorization to attacker host

Updated under an hour ago (Oct 28, 2026, 12:30 AM ET)

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It affects ruby-oauth oauth2. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for ruby-oauth oauth2

Exploited in the last 30 days

OAuth2 is a Ruby wrapper for the OAuth 2.0 and 2.1 authorization frameworks, including OpenID Connect (OIDC). From 0.4.0 to 2.0.21, a protocol-relative redirect Location returned to OAuth2::Client#request overrides the request authority, so the bearer Authorization header is sent to an attacker-controlled host, leaking the credential. This issue is fixed in version 2.0.22.

CVSS: 8.6 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N
Weakness (CWE): CWE-200, CWE-601
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Awaiting Analysis
Record last updated: Oct 5, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

ruby-oauth oauth2 ruby_oauth:oauth2 (from the name)	from 0.4.0, < 2.0.22	CNA record

References

References

https://github.com/ruby-oauth/oauth2/security/advisories/GHSA-pp92-crg2-gfv9	x-refsource-confirm
https://github.com/ruby-oauth/oauth2/commit/0f0a474f1b38453e119e660c2daca742d4378ce9	x-refsource-misc
https://github.com/ruby-oauth/oauth2/releases/tag/v2.0.22	x-refsource-misc
https://lists.debian.org/debian-lts-announce/2026/10/msg00014.html

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.