http4k: `DigestAuthProvider.verify` did not bind to request URI

Impact

An issue in DigestAuthProvider.verify:

The uri parameter in the client's Authorization: Digest … response was not checked against the actual request URL. A captured Digest authentication response could be replayed against any other URL served by the same realm, breaking the per-request-URL binding the Digest scheme assumes.

Who is affected: any application using http4k-security-digest for HTTP Digest authentication. The bug has been present since DigestAuthProvider was introduced (commit 8a52b615b1, 2021).

Patches

| Line | Fixed in | Edition | |------|----------|---------| | v6.x (Community) | 6.50.0.0 | Community | | v5.x (LTS) | 5.42.0.0 | Enterprise — contact [email protected] (if Digest auth is present in your v5.x line) | | v4.x (LTS) | 4.51.0.0 | Enterprise — contact [email protected] (if Digest auth is present in your v4.x line) |

The fix:

• Rejects credentials whose uri parameter does not match the request URL.

Workarounds

For deployments that cannot upgrade immediately:

• URI binding gap: place Digest auth behind a reverse proxy that pins requests to a single URL.

References

• Vulnerability first present: 8a52b615b1
• URI binding fix: 725f1b9697
• Fix release: v6.50.0.0
• Background: RFC 7616 — HTTP Digest Access Authentication