CVE-2026-15816
Publication date 7 August 2026
Last updated 24 September 2026
Ubuntu priority
Description
A flaw was found in dracut. The die() error-handling function writes its message into a shell script under the initramfs emergency-hook directory without properly shell-quoting it. When the message contains data derived from the DHCP ROOT_PATH option, an attacker on the adjacent network who controls a rogue DHCP server can inject a command-substitution sequence that executes as root the next time dracut sources its emergency hook scripts during standard boot-failure handling.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| dracut | 26.04 LTS resolute |
Fixed 110-11ubuntu0.1
|
| 24.04 LTS noble |
Vulnerable
|
|
| 22.04 LTS jammy |
Vulnerable
|
|
| 20.04 LTS focal |
Vulnerable
|
|
| 18.04 LTS bionic |
Vulnerable
|
|
| 16.04 LTS xenial |
Vulnerable
|
Severity score breakdown
CVSS version: CVSS v3.0
Base score
7.5 · High
Vector: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
References
Related Ubuntu Security Notices (USN)
- USN-8758-1
- dracut vulnerability
- 14 September 2026
Other references
- https://www.cve.org/CVERecord?id=CVE-2026-15816
- https://access.redhat.com/security/cve/CVE-2026-15816
- https://bugzilla.redhat.com/show_bug.cgi?id=2459963
- https://bugzilla.redhat.com/show_bug.cgi?id=2500889
- https://github.com/dracutdevs/dracut/blob/master/modules.d/40network/netroot.sh
- https://github.com/dracutdevs/dracut/blob/master/modules.d/99base/dracut-lib.sh