Remote code execution via malicious DHCP options
Summary
| CVE | CVE-2026-42511 |
|---|---|
| State | PUBLISHED |
| Assigner | freebsd |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-04-30 07:16:37 UTC |
| Updated | 2026-05-01 16:16:32 UTC |
| Description | The BOOTP file field is written to the lease file without escaping embedded double-quotes, allowing injection of arbitrary dhclient.conf directives. When the lease file is subsequently re-parsed by dhclient, e.g., after a system restart, an attacker-controlled field from the lease is passed to dhclient-script(8), which evaluates it. A rogue DHCP server may be able to execute arbirary code as root on a system running dhclient. |
Risk And Classification
Primary CVSS: v3.1 8.1 HIGH from ADP
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS: 0.000450000 probability, percentile 0.135650000 (date 2026-05-05)
Problem Types: CWE-149 | CWE-149 CWE-149: Improper Neutralization of Quoting Syntax
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | ADP | DECLARED | 8.1 | HIGH | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | Secondary | 8.1 | HIGH | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
HighPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
HighCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Operating System | Freebsd | Freebsd | 13.5 | - | All | All |
| Operating System | Freebsd | Freebsd | 13.5 | beta3 | All | All |
| Operating System | Freebsd | Freebsd | 13.5 | p1 | All | All |
| Operating System | Freebsd | Freebsd | 13.5 | p10 | All | All |
| Operating System | Freebsd | Freebsd | 13.5 | p11 | All | All |
| Operating System | Freebsd | Freebsd | 13.5 | p12 | All | All |
| Operating System | Freebsd | Freebsd | 13.5 | p2 | All | All |
| Operating System | Freebsd | Freebsd | 13.5 | p3 | All | All |
| Operating System | Freebsd | Freebsd | 13.5 | p4 | All | All |
| Operating System | Freebsd | Freebsd | 13.5 | p5 | All | All |
| Operating System | Freebsd | Freebsd | 13.5 | p6 | All | All |
| Operating System | Freebsd | Freebsd | 13.5 | p7 | All | All |
| Operating System | Freebsd | Freebsd | 13.5 | p8 | All | All |
| Operating System | Freebsd | Freebsd | 13.5 | p9 | All | All |
| Operating System | Freebsd | Freebsd | 14.3 | - | All | All |
| Operating System | Freebsd | Freebsd | 14.3 | p1 | All | All |
| Operating System | Freebsd | Freebsd | 14.3 | p10 | All | All |
| Operating System | Freebsd | Freebsd | 14.3 | p11 | All | All |
| Operating System | Freebsd | Freebsd | 14.3 | p2 | All | All |
| Operating System | Freebsd | Freebsd | 14.3 | p3 | All | All |
| Operating System | Freebsd | Freebsd | 14.3 | p4 | All | All |
| Operating System | Freebsd | Freebsd | 14.3 | p5 | All | All |
| Operating System | Freebsd | Freebsd | 14.3 | p6 | All | All |
| Operating System | Freebsd | Freebsd | 14.3 | p7 | All | All |
| Operating System | Freebsd | Freebsd | 14.3 | p8 | All | All |
| Operating System | Freebsd | Freebsd | 14.3 | p9 | All | All |
| Operating System | Freebsd | Freebsd | 14.4 | - | All | All |
| Operating System | Freebsd | Freebsd | 14.4 | p1 | All | All |
| Operating System | Freebsd | Freebsd | 14.4 | p2 | All | All |
| Operating System | Freebsd | Freebsd | 14.4 | rc1 | All | All |
| Operating System | Freebsd | Freebsd | 15.0 | - | All | All |
| Operating System | Freebsd | Freebsd | 15.0 | p1 | All | All |
| Operating System | Freebsd | Freebsd | 15.0 | p2 | All | All |
| Operating System | Freebsd | Freebsd | 15.0 | p3 | All | All |
| Operating System | Freebsd | Freebsd | 15.0 | p4 | All | All |
| Operating System | Freebsd | Freebsd | 15.0 | p5 | All | All |
| Operating System | Freebsd | Freebsd | 15.0 | p6 | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | FreeBSD | FreeBSD | affected 15.0-RELEASE p7 release | Not specified |
| CNA | FreeBSD | FreeBSD | affected 14.4-RELEASE p3 release | Not specified |
| CNA | FreeBSD | FreeBSD | affected 14.3-RELEASE p12 release | Not specified |
| CNA | FreeBSD | FreeBSD | affected 13.5-RELEASE p13 release | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| security.freebsd.org/advisories/FreeBSD-SA-26:12.dhclient.asc | [email protected] | security.freebsd.org | Vendor Advisory |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Joshua Rogers of AISLE Research Team (en)
There are currently no legacy QID mappings associated with this CVE.