CVE-2026-18103

Medium

Description

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.

SeverityMedium
CVSS4.9
Exploit probability—
ProductRed Hat Enterprise Linux 6
PublishedAug 5, 2026
First seenAug 5, 2026
Weakness typeCWE-120CWE-120

How to fix

Sources list no fixed version or patch link for this vulnerability.

Affected products

ProductAffected versionsFixed in
Red Hat Red Hat Enterprise Linux 6No range specified—
Red Hat Red Hat Enterprise Linux 7No range specified—
Red Hat Red Hat Enterprise Linux 8No range specified—
Red Hat Red Hat Enterprise Linux 9No range specified—

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