CVE-2026-54147

http4k: `DigestAuthProvider.verify` ignored configured algorithm and did not bind to request URI

MEDIUM
6.5
CVSS Score
Published: September 18, 2026 at 04:10 PM UTC
Updated: September 24, 2026 at 09:37 PM UTC
1 product affected across 1 vendorHTTP4K

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Severity
MEDIUM6.5
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 4.51.0.0v < 5.42.0.0v < 6.50.0.0
Affected range stops below 4.51.0.0, so it looks safe — our inference, not a vendor statement
Affected range stops below 5.42.0.0, so it looks safe — our inference, not a vendor statement
Affected range stops below 6.50.0.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

6.5MEDIUMGitHub_M
Attack Vector
NETWORK
Complexity
HIGH
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-327

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