HTTP Header Injection Affecting github.com/oauth2-proxy/oauth2-proxy/pkg/middleware package, versions <7.13.0
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- published12 Nov 2025
- disclosed10 Nov 2025
- creditSid 猫
Introduced: 10 Nov 2025
NewCVE-2025-64484 Â (opens in a new tab)How to fix?
Upgrade github.com/oauth2-proxy/oauth2-proxy/pkg/middleware to version 7.13.0 or higher.
Overview
Affected versions of this package are vulnerable to HTTP Header Injection via the processing of HTTP headers containing underscores, which are normalized to dashes by certain upstream applications. Authenticated users can escalate privileges by injecting specially crafted X_Forwarded-* headers that bypass filtering logic. This is only exploitable if the upstream application normalizes underscores to dashes in HTTP headers.
Workaround
This vulnerability can be mitigated by ensuring that filtering and processing logic in upstream services do not treat underscores and hyphens in headers as equivalent.