Impact
On boot, the Pillar container checks for /config/authorizedkeys. If present with a valid public key, it enables SSH on port 22 with root login. The /config partition is not protected by measured boot, is mutable and unencrypted.
This enables an attacker with physical access to the device to take out the disk, modify the /config partition using a separate server, then insert it, without the inserted key being flagged as an integrity voilation my measured boot and remote attestation.
Patches
Patched in 9.4.3-lts
Workarounds
None (apart from preventing physical access to the device)
Impact
VTPM server listens on port 8877, exposing limited TPM functionality. The server reads 4 bytes as a uint32 size header, then allocates that amount on the stack for incoming data. This allows Denial of Service attacks against the vTPM service.
An workload (a container or VM) running on EVE-OS can use this to generate a DOS against the vTPM service.
Patches
Fixed in 9.4.3-lts and 10.1.0
Workarounds
None
Impact
The vault key is sealed using SHA1 PCRs instead of SHA256 PCRs
Thus an attacker with physical access to an EVE-OS device can try to brute force creating a kernel or rootfs image which produces the same SHA1 PCR but with malicious content.
Patches
Fixed in 9.4.3-lts and 10.1.0
Workarounds
None
Impact
Measured boot validates BIOS, grub, kernel cmdline, and initrd but not the entire rootfs. Thus, an attacker can create an EVE-OS rootfs squashfs image with some files modified and take out the disk and replace the existing rootfs image without that being detected by measure boot and remote attestation.
Patches
Fixed in 8.6.0 and 8.12.1-lts
Workarounds
None
Impact PCR14 is not included in the list of PCRs that seal/unseal the vault key. Additionally, the vault key uses SHA1 PCRs instead of SHA256. Thus an attacker with physical access can take out the disk, use a different computer to modify the files in the /config partition, and re-insert the disk and boot without the change being detected by measured boot and remote attestation.
Patches
Fixed in EVE version 9.4.3-lts
Workarounds
None (apart from preventing physical access to the device)
Resources
https://help.zededa.com/hc/en-us/articles/43295940828827-TPM-PCR-Index-Security-Implications https://github.com/lf-edge/eve/commit/d9383a7ee4e1c39f5c8c6d4a63cb2ebd00695e8a