Vulnerability · Published Sep 21, 2023 · Assigned by ASRG
CVE-2023-43634 Config Partition Not Protected by Measured Boot
High 8.8
In plain English
A high-severity security flaw in EVE OS from LF-Edge, Zededa. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 6% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
When sealing/unsealing the “vault” key, a list of PCRs is used, which defines which PCRs are used. In a previous project, CYMOTIVE found that the configuration is not protected by the secure boot, and in response Zededa implemented measurements on the config partition that was mapped to PCR 13. In that process, PCR 13 was added to the list of PCRs that seal/unseal the key. In commit “56e589749c6ff58ded862d39535d43253b249acf”, the config partition measurement moved from PCR 13 to PCR 14, but PCR 14 was not added to the list of PCRs that seal/unseal the key. This change makes the measurement of PCR 14 effectively redundant as it would not affect the sealing/unsealing of the key. An attacker could modify the config partition without triggering the measured boot, this could result in the attacker gaining full control over the device with full access to the contents of the encrypted “vault”
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/lf-edge/eve | 0.0.0-20230519072751-977f42b07fa9 | GHSA-wc42-fcjp-v8vq |
| Go | github.com/lf-edge/eve | 0.0.0-20230519072751-977f42b07fa9 | GO-2026-4432 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| LF-Edge, Zededa | EVE OS | 0 – before 8.6.09.0.0 – before 9.5.0 |
Weakness: CWE-522, CWE-922 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H