---
cve: "CVE-2021-26102"
severity: "CRITICAL"
cvss: 9.8
epss: "16.8%"
vendor: "Fortinet"
kev: false
exploited: false
published: "2024-12-19 14:15:05"
tags: [cve, security, critical]
source: tsecurity.de CVE-Dossier
exported: "2026-09-03T11:06:27+02:00"
---

# CVE-2021-26102

> 9.8 CRITICAL

## Beschreibung

A relative path traversal vulnerability (CWE-23) in FortiWAN version 4.5.7 and below, 4.4 all versions may allow a remote non-authenticated attacker to delete files on the system by sending a crafted POST request. In particular, deleting specific configuration files will reset the Admin password to its default value.

## CVSS-Vektor

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

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

## Schwachstellen-Klasse

- **CWE-23** — Relative Path Traversal
  The product uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize sequences such as ".." that can resolve to a location that is outside of that directory.

## Angriffsmuster (CAPEC)

- [CAPEC-76 — Manipulating Web Input to File System Calls](https://capec.mitre.org/data/definitions/76.html) _(Severity: Very High)_
- [CAPEC-139 — Relative Path Traversal](https://capec.mitre.org/data/definitions/139.html) _(Severity: High)_

## Referenzen

- <https://fortiguard.fortinet.com/psirt/FG-IR-21-048>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2021-26102) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_