CVE-2026-69212mediumCWE-200CWE-319

CVE-2026-69212: medium-severity vulnerability in http4s

Http4s: FollowRedirect middleware leaks credentials over https->http same-authority redirect

Published

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33Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 5.9epss 0.3%
from disclosure to weaponsame day
Published on NVDSep 15
1st PoCJun 28
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.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Affected products
http4s · http4s
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