Vulnerability · Published Sep 15, 2026 · Assigned by GitHub_M
CVE-2026-69206Http4s: DigestAuth allows replay of captured requests
Medium 5.9
In plain English
A medium-severity security flaw in http4s from http4s. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 34% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Maven | org.http4s:http4s-ember-core_2.12 | 0.23.35 | GHSA-9xww-74xv-gjfp |
| Maven | org.http4s:http4s-ember-core_2.13 | 0.23.35 | GHSA-9xww-74xv-gjfp |
| Maven | org.http4s:http4s-ember-core_2.13 | 1.0.0-M47 | GHSA-9xww-74xv-gjfp |
| Maven | org.http4s:http4s-ember-core_3 | 0.23.35 | GHSA-9xww-74xv-gjfp |
| Maven | org.http4s:http4s-ember-core_3 | 1.0.0-M47 | GHSA-9xww-74xv-gjfp |
Affected products (as reported)
Weakness: CWE-294 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
References
- https://github.com/http4s/http4s/security/advisories/GHSA-9xww-74xv-gjfp x_refsource_CONFIRM
- https://github.com/http4s/http4s/commit/7f065101c45f3d86bc105e8fc6323c2c4a11471f x_refsource_MISC
- https://github.com/http4s/http4s/releases/tag/v0.23.35 x_refsource_MISC
- https://github.com/http4s/http4s/releases/tag/v1.0.0-M47 x_refsource_MISC