CVE-2026-69206
Http4s: DigestAuth allows replay of captured requests
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, DigestAuth replay protection records lastNc plus one instead of the highest nonce-count value it has accepted. When a legitimate client sends noncontiguous nc values because of parallel or retried requests, the stored counter remains below the accepted maximum, allowing a passive observer to replay a captured Authorization header multiple times. Successful replays execute authenticated requests, including state-changing operations, as the captured user. This issue is fixed in versions 0.23.35 and 1.0.0-M47.
| CWE | CWE-294 |
| Vendor | http4s |
| Product | http4s |
| Published | Sep 15, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
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-9xww-74xv-gjfp github.com: https://github.com/http4s/http4s/commit/7f065101c45f3d86bc105e8fc6323c2c4a11471f 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