CVE-2026-124740

medium

Description

A flaw was found in BusyBox's udhcpc6 DHCPv6 client. A malicious server on the local network can trigger a use-after-free condition by responding with a crafted Dynamic Host Configuration Protocol for IPv6 (DHCPv6) reply packet lacking usable address options. This issue causes the client to read stale heap memory, which can result in a Denial of Service (DoS) due to an application crash or disclose previously assigned network address data in subsequent discovery requests.

References

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-123358

https://bugzilla.redhat.com/show_bug.cgi?id=2571616

https://access.redhat.com/security/cve/CVE-2026-124740

Details

Source: Mitre, NVD

Published: 2026-11-11

Updated: 2026-11-12

Risk Information

CVSS v2

Base Score: 3.3

Vector: CVSS2#AV:A/AC:L/Au:N/C:N/I:N/A:P

Severity: Low

CVSS v3

Base Score: 4.3

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

Severity: Medium

EPSS

EPSS: 0.00203