CVE-2026-56113 | dhcpcd through 10.3.2, fixed in commit 5733d3c, contains a h… | CVSS 5.3 MEDIUM

Description

dhcpcd through 10.3.2, fixed in commit 5733d3c, contains a heap use-after-free vulnerability that allows unauthenticated same-link attackers to crash the daemon by sending a crafted DHCPv6 RENEW reply with RFC6603 OPTION_PD_EXCLUDE and both preferred and valid lifetimes set to zero. Attackers acting as or impersonating a DHCPv6 server can trigger dhcp6_deprecatedele() to free a delegated child address while an outer TAILQ_FOREACH_SAFE iterator in dhcp6_deprecateaddrs() still holds the freed pointer, causing a use-after-free when TAILQ_REMOVE is reached.

Metadata

CVE ID: CVE-2026-56113
State: PUBLISHED
Assigner: VulnCheck
Reserved: 2026-06-18 19:15 UTC
Published: 2026-06-23 16:05 UTC
Last updated: 2026-06-23 17:58 UTC
Primary CWE: CWE-416
Use After Free
Vendor / Product: NetworkConfiguration / dhcpcd
Sources: cve.org · NVD

Severity & Metrics

5.3 MEDIUM CVSS 3.1

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

SSVC — CISA Coordinator

Exploitation: none
Automatable: no
Tech. Impact: partial

Affected products (1)

Vendor	Product	Platform	Versions
NetworkConfiguration	dhcpcd	—	0 ≤ 10.3.2, 5733d3c59a5651f64357ac11c98b4f39895c8d25

Weakness (CWE)

CWE	Source	Description
CWE-416	cna	Use After Free

CVSS scores (2)

Score	Severity	Version	Source	Vector
6.0	MEDIUM	4.0	cna	CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
5.3	MEDIUM	3.1	cna	CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

References (2)