CVE-2026-42512: Remotely triggerable out-of-bounds heap write in dhclient
As dhclient is building an environment to pass to dhclient-script, it may need to resize the array of string pointers. The code which expands the array incorrectly calculates its new size when requesting memory, resulting in a heap buffer overrun.
A specially crafted packet can cause dhclient to overrun its buffer of environment entries. This can result in a crash, but it may be possible to leverage this bug to achieve remote code execution.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-42512?
CVE-2026-42512 has been classified with a high severity due to its potential for exploitation, leading to remote code execution.
How do I fix CVE-2026-42512?
To fix CVE-2026-42512, ensure you update the affected versions of dhclient to the latest patched versions provided by your vendor.
What versions of dhclient are affected by CVE-2026-42512?
CVE-2026-42512 affects multiple versions of Internet Systems Consortium dhclient and various FreeBSD versions including 13.5 and 14.3.
Can CVE-2026-42512 be exploited remotely?
Yes, CVE-2026-42512 can be remotely triggered, allowing an attacker to exploit the vulnerability without physical access.
What could be the impact of CVE-2026-42512?
The impact of CVE-2026-42512 includes potential system crashes or remote code execution, compromising system security.