SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2026-42511

The BOOTP file field is written to the lease file without escaping embedded double-quotes, allowing injection of arbitrary dhclient.conf directives.

HIGH 8.1EPSS 0.43%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.43%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1
8.1 HIGHCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
0.43% probability · 36th percentile
CISA KEV
Not listed
Weakness
CWE-149
Affected
freebsd/freebsd
Source
secteam@freebsd.org

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.