dhcpcd Heap Use-After-Free via Control Socket Handling_CVE-2026-56117

5.7 / 10

MEDIUM

CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Description

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.

Basic Information

ID CVE-2026-56117

Source VulnCheck

Published Jun 23, 2026 at 16:14

Affected Product

Vendor NetworkConfiguration

Product dhcpcd

Affected Versions NetworkConfiguration dhcpcd 0

CWE Classification

CWE-416

References

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    "published": "2026-06-23T16:14:31.918Z",
    "modified": "2026-06-23T16:14:31.918Z",
    "type": "cve",
    "title": "dhcpcd Heap Use-After-Free via Control Socket Handling",
    "source": "VulnCheck",
    "references": "https://github.com/NetworkConfiguration/dhcpcd/commit/78ea09ed1633a583dbcde6e7bab9df4639ec8a34\nhttps://www.vulncheck.com/advisories/dhcpcd-heap-use-after-free-via-control-socket-handling",
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