CVE-2026-56117

dhcpcd through 10.3.2, fixed in commit 78ea09e, contains a heap use-after-free vulnerability in the control socket handling within src/control.c that allows local unprivileged attackers to trigger memory corruption when privilege separation is disabled. Attackers can connect to the control socket and send a privileged command such as -x, causing control_recvdata() to free the client object while the same READ+HANGUP event subsequently reaches control_hangup() with the stale pointer, resulting in a use-after-free condition exploitable in deployments using --disable-privsep or where privsep initialization has failed with the control socket operating in mode 0666.

CVSS v3 4.7 MEDIUM

4.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.0 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/NetworkConfiguration/dhcpcd/commit/78ea09ed1633a583dbcde6e7bab9df4639ec8a34	Patch
https://www.vulncheck.com/advisories/dhcpcd-heap-use-after-free-via-control-socket-handling	Third Party Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-06-23 17:17

Updated : 2026-07-14 22:17

NVD link : CVE-2026-56117

Mitre link : CVE-2026-56117

CVE.ORG link : CVE-2026-56117

JSON object : View

Products Affected

dhcpcd_project

dhcpcd

CWE

CWE-416

Use After Free

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