---
cve: "CVE-2026-18103"
severity: "MEDIUM"
cvss: 4.9
epss: "40%"
vendor: "Generic Security"
kev: false
exploited: false
published: "2026-08-05 00:16:59"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-18T04:55:36+02:00"
---

# CVE-2026-18103

> 4.9 MEDIUM

## Beschreibung

A flaw was found in dhcp-server. A remote attacker with network access to the OMAPI (Open Management Application Programming Interface) port, especially if not secured with TSIG (Transaction Signature) key authentication, could send a specially crafted lease creation request. This request, containing an overly long InfiniBand MAC address, triggers a buffer overflow in the `print_hw_addr()` function. Successful exploitation leads to a persistent denial of service (DoS), causing the `dhcpd` service to crash and preventing it from restarting without manual intervention.

## CVSS-Vektor

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

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

## Referenzen

- <https://access.redhat.com/security/cve/CVE-2026-18103>
- <https://bugzilla.redhat.com/show_bug.cgi?id=2508081>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-18103) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_