CVE-2026-18103 (GCVE-0-2026-18103)

Vulnerability from cvelistv5 – Published: 2026-08-04 23:08 – Updated: 2026-11-06 18:08
VLAI
Title
Dhcp-server: dhcp-server: persistent denial of service due to buffer overflow via omapi
Summary
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.
Severity
4.9 (Medium)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-05 13:58 UTC
CWE
  • CWE-120 - Buffer Copy without Checking Size of Input
Assigner
redhat CNA
References
URL Tags
https://access.redhat.com/security/cve/CVE-2026-18103 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2508081 issue-trackingx_refsource_REDHAT
Impacted products
Date Public
2026-07-28 17:35
Credits
This issue was discovered by Martin Osvald (Red Hat).
Show details on NVD website
To clipboard 

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