This page tracks the Debian fix status. The vulnerability itself is described on the main CVE page. View CVE-2026-56114 →

DEBIAN-CVE-2026-56114

dhcpcd through 10.3.2, fixed in commit 2f00c7b, contains a one-byte stack out-of-bounds write vulnerability in dhcp6_makemessage() in src/dhcp6.c that...

Original description

The description as published by the source.

dhcpcd through 10.3.2, fixed in commit 2f00c7b, contains a one-byte stack out-of-bounds write vulnerability in dhcp6_makemessage() in src/dhcp6.c that allows unauthenticated same-link attackers to write beyond a fixed local buffer by serializing an oversized RFC6603 OPTION_PD_EXCLUDE option body. Attackers can send a crafted DHCPv6 ADVERTISE message containing an IA_PD IAPREFIX /0 with a valid OPTION_PD_EXCLUDE using an exclude prefix length of /121 through /128 to trigger the out-of-bounds write and potentially corrupt adjacent stack memory.

Source: OSV.dev (Open Source Vulnerabilities) OSV

Affected packages

Debian:13 dhcpcd

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:10.1.0-11+deb13u3"}]}]

Debian:14 dhcpcd

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:10.3.2-4"}]}]

Debian:12 dhcpcd5

[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"9.4.1-24~deb12u5"}]}]

References

advisory security-tracker.debian.org