Vulnerability in Http4k
CVE-2026-54147
http4k is a functional toolkit for Kotlin HTTP applications. Prior to 4.51.0.0, 5.42.0.0, and 6.50.0.0, DigestAuthProvider.verify in http4k-security-digest ignores its configured algorithm parameter and verifies every Digest response with hardcoded MD5. Deployments configured for SHA-256 therefore receive weaker MD5-based verification, exposing Digest authentication to collision-related attack paths that depend on the hash function's collision resistance. This issue is fixed in versions 4.51.0.0, 5.42.0.0, and 6.50.0.0.
Vulnerability class: POODLE (CVE-2014-3566)
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:N.
Affected products
- Http4k — versions < 4.51.0.0, >= 5.0.0.0, < 5.42.0.0, >= 6.0.0.0, < 6.50.0.0
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_CONFIRM)
Frequently asked questions
- What is CVE-2026-54147?
- CVE-2026-54147 is a medium-severity vulnerability in Http4k, classified under Use of a Broken or Risky Cryptographic Algorithm. CVSS score: 6.5/10. Published 2026-09-18.
- How severe is CVE-2026-54147?
- Medium severity. CVSS v3 base score is 6.5 out of 10.