Edge Virtualization Engine
CVE-2023-43631
HIGH
Severity by source
AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Lifecycle Timeline
1DescriptionNVD
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.
AnalysisAI
On boot, the Pillar eve container checks for the existence and content of “/config/authorized_keys”. Rated high severity (CVSS 8.8), this vulnerability is low attack complexity. No vendor patch available.
Technical ContextAI
This vulnerability is classified as Insufficiently Protected Credentials (CWE-522), which allows attackers to obtain user credentials due to weak protection mechanisms. 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. Affected products include: Linuxfoundation Edge Virtualization Engine. Version information: version 9.0.0.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Hash passwords with strong algorithms (bcrypt, argon2), encrypt credentials in transit and at rest, never log credentials.
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Same weakness CWE-522 – Insufficiently Protected Credentials
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External POC / Exploit Code
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