---
cve: "CVE-2026-9547"
severity: "HIGH"
cvss: 7.4
epss: "33%"
vendor: "curl"
kev: false
exploited: false
published: "2026-07-03 07:16:25"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-09-13T22:20:28+02:00"
---

# CVE-2026-9547

> 7.4 HIGH

## Beschreibung

When a libcurl-based application performs transfers via `SCP://` or `SFTP://`
and utilizes the `CURLOPT_SSH_KEYFUNCTION` callback, it may silently accept an
untrusted server. This vulnerability occurs when a server presents a host key
type that does not match the specific key type already recorded for that host
in the `known_hosts` file. Instead of rejecting the mismatch, the callback
mechanism fails to properly enforce the restriction, allowing the connection
to succeed without warning and risking a potential man-in-the-middle attack.

## CVSS-Vektor

```
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Hoch | good |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Hoch | bad |
| I Integrität | Hoch | bad |
| A Verfügbarkeit | Keine | good |

## Patch verfügbar (OSV)

- 68720b4837284335b2d63cb358f8f6ce65f5bc55 (Commit)

## Referenzen

- <https://curl.se/docs/CVE-2026-9547.json>
- <https://curl.se/docs/CVE-2026-9547.html>
- <https://hackerone.com/reports/3751712>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-9547) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_