High severity · published Sep 21, 2023
CVE-2023-43631
On boot, the Pillar eve container checks for the existence and content of “/config/authorized_keys”
8.8
CVSS
0.2%
EPSS
No
On KEV
Description
On boot, the Pillar eve container checks for the existence and content of
“/config/authorized_keys”.
If the file is present, and contains a supported public key, the container will go on to open
port 22 and enable sshd with the given keys as the authorized keys for root login.
An attacker could easily add their own keys and gain full control over the system without
triggering the “measured boot” mechanism implemented by EVE OS, and without marking
the device as “UUD” (“Unknown Update Detected”).
This is because the “/config” partition is not protected by “measured boot”, it is mutable, and
it is not encrypted in any way.
An attacker can gain full control over the device without changing the PCR values, thus not
triggering the “measured boot” mechanism, and having full access to the vault.
Note:
This issue was partially fixed in these commits (after disclosure to Zededa), where the config
partition measurement was added to PCR13:
• aa3501d6c57206ced222c33aea15a9169d629141
• 5fef4d92e75838cc78010edaed5247dfbdae1889.
This issue was made viable in version 9.0.0 when the calculation was moved to PCR14 but it was not included in the measured boot.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 6% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EV
Edge Virtualization Engine · Linuxfoundation
before 8.6.0; 9.0.0 before 9.5.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-43631
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-43631
asrg.io
https://asrg.io/security-advisories/cve-2023-43631/
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