TI-2026-40499 Aliases CVE-2026-56117 GHSA-p284-r695-7gxf

dhcpcd Heap Use-After-Free via Control Socket Handling

LOW 25CWE-416Published 2026-06-23 · Updated 2026-07-28

Key facts

Attack vector: Local
Privileges required: Low
User interaction: None
Attack complexity: Low
Attack requirements: Present
Impact type: Denial of service
Confidentiality · integrity · availability: None · None · High
Fix status: Partial Red Hat: 1 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00135 3rd percentileScored 2026-11-07

Fix Partial Red Hat: 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
NetworkConfiguration	dhcpcd	up to 10.3.2	—	Patch available	CNA

dhcpcd VendorNetworkConfiguration Affected up to 10.3.2 Fixed in — Patch available CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:dhcpcd_project:dhcpcd::::::::	up to 10.3.2	Vulnerable	NetworkConfiguration

cpe:2.3:a:dhcpcd_project:dhcpcd:*:*:*:*:*:*:*:* Versions up to 10.3.2 Vulnerable ·NetworkConfiguration

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

Product	Status	Plan or fix
Red Hat Enterprise Linux 10	Affected	No fix yet: Fix deferred

Timeline

2026-10-02 Threatist record created from CVE-2026-56117
2026-10-03 Alias added: GHSA-p284-r695-7gxf

References

Patch 1

https://github.com/NetworkConfiguration/dhcpcd/commit/78ea09ed1633a583dbcde6e7bab9df4639ec8a34

TI-2019-08650 dhcpcd before 7.2.1 contains a buffer overflow in dhcp6_findna in dhcp6.c when reading NA/TA addresses. CVSS 3.0CRITICAL 9.8
TI-2016-01390 dhcpcd before 6.10.0, as used in Android 4.x before 4.4.4, 5.0.x before 5.0.2, 5.1.x… CVSS 3.0CRITICAL 9.8
TI-2019-08823 dhcp6.c in dhcpcd before 6.11.7 and 7.x before 7.2.2 has a buffer over-read in the D6_OPTION_PD_EXCLUDE feature. CVSS 3.1CRITICAL 9.8
TI-2016-01391 dhcpcd before 6.10.0 allows remote attackers to cause a denial of service (invalid read… CVSS 3.0HIGH 7.5
TI-2012-05402 The decode_search function in dhcp.c in dhcpcd 3.x does not properly free allocated… CVSS 3.0HIGH 7.5
TI-2012-05401 The decode_search function in dhcp.c in dhcpcd 3.x allows remote DHCP servers to cause a… CVSS 3.0HIGH 7.5

See all 15 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences