---
cve: "CVE-2026-27588"
severity: "HIGH"
cvss: 7.7
epss: "0.4%"
vendor: "caddyserver"
kev: false
exploited: false
published: "2026-02-24 16:28:28"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-20T20:05:54+02:00"
---

# CVE-2026-27588

> 7.7 HIGH · 🧪 PoC

## Beschreibung

Caddy is an extensible server platform that uses TLS by default. Prior to version 2.11.1, Caddy's HTTP `host` request matcher is documented as case-insensitive, but when configured with a large host list (>100 entries) it becomes case-sensitive due to an optimized matching path. An attacker can bypass host-based routing and any access controls attached to that route by changing the casing of the `Host` header. Version 2.11.1 contains a fix for the issue.

## CVSS-Vektor

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

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

## Patch verfügbar (OSV)

- 6610e2f1bd8f54853006eefd3849c9965190e57f (Commit)

## Referenzen

- <https://github.com/caddyserver/caddy/security/advisories/GHSA-x76f-jf84-rqj8>
- <https://github.com/caddyserver/caddy/releases/tag/v2.11.1>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-27588) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_