CVE-2026-56116

dhcpcd through 10.3.2, fixed in commit 708b4a5, contains a memory leak vulnerability in the IPv6 Router Advertisement route information handling that allows an unauthenticated same-link attacker to cause denial of service by sending crafted Router Advertisements. Attackers can repeatedly send Router Advertisements containing Route Information options with a lifetime of zero, triggering unfreed allocations in routeinfo_findalloc() that cause linear memory exhaustion and eventual daemon crash.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/NetworkConfiguration/dhcpcd/commit/708b4a56bae080a5b18c2e0c4c6fbe103131a2b0	Patch
https://www.vulncheck.com/advisories/dhcpcd-memory-leak-dos-via-ipv6-router-advertisement-handling	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:dhcpcd_project:dhcpcd:*:*:*:*:*:*:*:*

History

28 Jun 2026, 00:27

Type	Values Removed	Values Added
CPE		cpe:2.3:a:dhcpcd_project:dhcpcd::::::::
References	~~() https://github.com/NetworkConfiguration/dhcpcd/commit/708b4a56bae080a5b18c2e0c4c6fbe103131a2b0 -~~	() https://github.com/NetworkConfiguration/dhcpcd/commit/708b4a56bae080a5b18c2e0c4c6fbe103131a2b0 - Patch
References	~~() https://www.vulncheck.com/advisories/dhcpcd-memory-leak-dos-via-ipv6-router-advertisement-handling -~~	() https://www.vulncheck.com/advisories/dhcpcd-memory-leak-dos-via-ipv6-router-advertisement-handling - Third Party Advisory
First Time		Dhcpcd Project Dhcpcd Project dhcpcd

23 Jun 2026, 17:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-23 17:17

Updated : 2026-07-14 22:17

NVD link : CVE-2026-56116

Mitre link : CVE-2026-56116

CVE.ORG link : CVE-2026-56116

JSON object : View

Products Affected

dhcpcd_project

dhcpcd

CWE

CWE-401

Missing Release of Memory after Effective Lifetime

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