---
cve: "CVE-2026-100834"
severity: "HIGH"
cvss: 8.2
epss: "0.3%"
vendor: "http4k"
kev: false
exploited: false
published: "2026-09-27 02:17:21"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-10-01T09:01:30+02:00"
---

# CVE-2026-100834

> 8.2 HIGH · 🧪 PoC

## Beschreibung

http4k's Digest authentication module (org.http4k:http4k-security-digest) before versions 6.48.0.0, 5.42.0.0 and 4.51.0.0 defaults the nonceVerifier parameter of ServerFilters.DigestAuth and DigestAuthProvider to { true }, so every nonce is accepted regardless of its value, age, or prior use. Applications relying on this default have no replay protection on Digest authentication: an attacker who can capture a valid 'Authorization: Digest' response (for example by observing network traffic or reading logs) can replay it indefinitely against the same protected resource.

## CNA-Record (Kanon, cvelistV5)

- CNA: **VulnCheck**
- State: PUBLISHED
- Stand: 2026-09-30 17:03:58
- CNA-CVSS: **8.2** (`CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N`)

## CISA-Anreicherung (vulnrichment/ADP)

- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **none**
  - Automatable: **no**
  - Technical Impact: **partial**

## CVSS-Vektor

```
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |

## Patch verfügbar (OSV)

- 7adc55e0662f69a6ca111094cf5e04a88da8d87c (Commit)
- e41f40814305510d4f82e30bb0bcd12b9928292e (Commit)

## Referenzen

- <https://github.com/http4k/http4k/security/advisories/GHSA-c7jm-38gq-h67h>
- <https://github.com/http4k/http4k/commit/8a52b615b1>
- <https://github.com/http4k/http4k/commit/4f904b4692>
- <https://www.vulncheck.com/advisories/http4k-before-6.48.0.0-digest-authentication-replay-protection-bypass>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-100834) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_