---
cve: "CVE-2026-86104"
severity: "HIGH"
cvss: 8.7
epss: "0.4%"
vendor: "WatchGuard"
kev: false
exploited: false
published: "2026-09-30 00:16:36"
tags: [cve, security, high]
source: tsecurity.de CVE-Dossier
exported: "2026-10-27T19:52:51+01:00"
---

# CVE-2026-86104

> 8.7 HIGH

## Beschreibung

An uncontrolled resource consumption vulnerability in the Fireware OS login process (wgagent) allows a remote, unauthenticated attacker to cause a denial of service by sending a specially crafted request.

## CNA-Record (Kanon, cvelistV5)

- CNA: **WatchGuard**
- State: PUBLISHED
- Stand: 2026-09-30 15:28:12
- CNA-CVSS: **8.7** (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)

## CISA-Anreicherung (vulnrichment/ADP)

- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **none**
  - Automatable: **yes**
  - Technical Impact: **partial**

## CVSS-Vektor

```
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/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 |

## Schwachstellen-Klasse

- **CWE-400** — Uncontrolled Resource Consumption
  The product does not properly control the allocation and maintenance of a limited resource.
- **CWE-409** — Improper Handling of Highly Compressed Data (Data Amplification)
  The product does not handle or incorrectly handles a compressed input with a very high compression ratio that produces a large output.
- **CWE-770** — Allocation of Resources Without Limits or Throttling
  The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.

## Angriffsmuster (CAPEC)

- [CAPEC-147 — XML Ping of the Death](https://capec.mitre.org/data/definitions/147.html) _(Severity: Medium)_
- [CAPEC-227 — Sustained Client Engagement](https://capec.mitre.org/data/definitions/227.html)
- [CAPEC-492 — Regular Expression Exponential Blowup](https://capec.mitre.org/data/definitions/492.html)

## ATT&CK-Techniken

- [T1499 — Endpoint Denial of Service](https://attack.mitre.org/techniques/T1499/)

## BSI-Hinweise (deutsch)

- [WatchGuard Fireware OS: Mehrere Schwachstellen](https://wid.cert-bund.de/portal/wid/sicherheitshinweis/WID-SEC-W-2026-3646) — _BSI-Einstufung: hoch_
  Ein entfernter Angreifer kann mehrere Schwachstellen in WatchGuard Fireware OS ausnutzen, um beliebigen Code auszuführen – einschließlich Code mit Root-Rechten –, Sicherheitsmaßnahmen zu umgehen, vertrauliche Daten offenzulegen oder zu manipulieren und Denial-of-Service-Zustände zu verursachen.

## Referenzen

- <https://psirt.watchguard.com/CVE-2026-86104>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/sicherheitsluecken/cve-2026-86104/) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_