CVE-2026-56117

dhcpcd Heap Use-After-Free via Control Socket Handling

MEDIUM
5.5
CVSS Score
Published: June 23, 2026 at 04:14 PM UTC
Updated: October 25, 2026 at 11:10 PM UTC
2 products affected across 2 vendorsDhcpcdProject Dhcpcd

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Severity
MEDIUM5.5
Exploit prediction
EPSS 0.1%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v ≤ 10.3.2
Vendor states this is fixed in 78ea09ed1633a583dbcde6e7bab9df4639ec8a34 (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
LOCAL
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-416

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