This page tracks the Ubuntu fix status. The vulnerability itself is described on the main CVE page. View CVE-2026-88833 →

UBUNTU-CVE-2026-88833

A flaw was found in BusyBox's udhcpc DHCP client. When processing raw DHCP packets, the client replaces the validated packet length with an attacker-c...

Original description

The description as published by the source.

A flaw was found in BusyBox's udhcpc DHCP client. When processing raw DHCP packets, the client replaces the validated packet length with an attacker-controlled value from the IP header without re-validating the minimum size. This leads to an integer underflow when subtracting header sizes, causing a subsequent memory copy with a massively oversized length. An attacker on the same network segment can send a specially crafted packet to crash the DHCP client, resulting in denial of service and loss of network connectivity.

Source: OSV.dev (Open Source Vulnerabilities) OSV