CVE-2026-69212

Medium

Description

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, The FollowRedirect client middleware strips Authorization and Cookie headers only when a redirect changes authority, but authority comparison excludes the URI scheme. A same-authority redirect from HTTPS to HTTP therefore preserves credentials and transmits them over a plaintext connection. An attacker who can induce the downgrade and observe the network can capture those sensitive headers from applications using FollowRedirect. This issue is fixed in versions 0.23.35 and 1.0.0-M47.

SeverityMedium
CVSS5.9
Exploit probability—
ProductHttp4s
PublishedSep 15, 2026
First seenSep 15, 2026

How to fix

Sources list no fixed version or patch link for this vulnerability.

Affected products

ProductAffected versionsFixed in
http4s http4s< 0.23.35, >= 1.0.0-M1, < 1.0.0-M47—

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