91
New Linux Security Flaw Uses Initramfs to Inject Malware
(www.omgubuntu.co.uk)
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
this post was submitted on 07 Jul 2025
91 points (100.0% liked)
Linux
8740 readers
307 users here now
A community for everything relating to the GNU/Linux operating system (except the memes!)
Also, check out:
Original icon base courtesy of lewing@isc.tamu.edu and The GIMP
founded 2 years ago
MODERATORS
It seems the issue here is that initramfs is not signed, which makes this attack possible.
If it is signed and an evil maid modifies the initramfs itself, it will break the secure boot process and the user will be notified that their system has been tampered with. This should indicate that the secure boot protection is working.
If initramfs is not signed and it drops to the debug shell, then the attacker can make any changes to your system without it affecting secure boot, since it has already passed the protection. At least that's my understanding when I read this.
This is true, unfortunately some Linux users have been conditioned to "just turn off Secure Boot" without understanding what this actually means and entails.
That makes sense. Would a signed initramfs be possible though? Since it's usually rebuilt after most system updates?
Depends on the OS, but you can generally have
mkinitcpiohandle generating new UKIs after updates and also have it trigger something likesbctlto re-sign images.