CVE-2026-56117
dhcpcd Heap Use-After-Free via Control Socket Handling
- State
- Published
- Severity
- 5.7 Medium
- Published
- Jun 23, 2026
- Updated
- Jul 28, 2026
- Reserved
- Jun 18, 2026
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 5.7 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 | VulnCheck |
| 3.1 | 4.7 Medium | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H | VulnCheck |
Weaknesses
- CWE-416 Use After Free
Affected Products
| Product | Versions |
|---|---|
dhcpcdNetworkConfiguration |
|
References
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