CVE-2026-69212
Http4s: FollowRedirect middleware leaks credentials over https->http same-authority redirect
CVSS Score
5.9
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-200 CWE-319 |
| Vendor | http4s |
| Product | http4s |
| Published | Sep 15, 2026 |
| Last Updated | Sep 15, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None
Affected Versions
http4s / http4s
< 0.23.35 >= 1.0.0-M1, < 1.0.0-M47
References
github.com: https://github.com/http4s/http4s/security/advisories/GHSA-2rgg-r783-mrx4 github.com: https://github.com/http4s/http4s/commit/6e825719b8d2f1538f2c49089c2dc81321a833b4 github.com: https://github.com/http4s/http4s/releases/tag/v0.23.35 github.com: https://github.com/http4s/http4s/releases/tag/v1.0.0-M47