VULNERABILITY INTELLIGENCE

CVE-2026-56114

CVSS score5.3 MEDIUM
EPSS probability0.27%
CISA KEVNot currently listed
Published2026-06-23
Last modified2026-10-25
CVSS vectorCVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Description

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.

Weakness classification

  • disclosure@vulncheck.com: CWE-787

Primary references