CVE-2024-43378 | calamares-nixos-extensions LUKS keyfile exposure regression on legacy BIOS systems

calamares-nixos-extensions provides Calamares branding and modules for NixOS, a distribution of GNU/Linux. Users who installed NixOS through the graphical installer who used manual disk partitioning to create a setup where the system was booted via legacy BIOS rather than UEFI; some disk partitions are encrypted; but the partitions containing either `/` or `/boot` are unencrypted; have their LUKS disk encryption key file in plain text either in `/crypto_keyfile.bin`, or in a CPIO archive attached to their NixOS initrd. `nixos-install` is not affected, nor are UEFI installations, nor was the default automatic partitioning configuration on legacy BIOS systems. The problem has been fixed in calamares-nixos-extensions 0.3.17, which was included in NixOS. The current installer images for the NixOS 24.05 and unstable (24.11) channels are unaffected. The fix reached 24.05 at 2024-08-13 20:06:59 UTC, and unstable at 2024-08-15 09:00:20 UTC. Installer images downloaded before those times may be vulnerable. The best solution for affected users is probably to back up their data and do a complete reinstallation. However, the mitigation procedure in GHSA-3rvf-24q2-24ww should work solely for the case where `/` is encrypted but `/boot` is not. If `/` is unencrypted, then the `/crypto_keyfile.bin` file will need to be deleted in addition to the remediation steps in the previous advisory. This issue is a partial regression of CVE-2023-36476 / GHSA-3rvf-24q2-24ww, which was more severe as it applied to the default configuration on BIOS systems.

Published: 2024-08-15 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2024-43378 is rated Low Risk (37.7/100): CVSS High severity, with low exploitation likelihood (EPSS 0.06%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2024-43378

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-11-21 0.04% 0.06% +0.02%
2 2025-11-18 0.08% 0.04% -0.04%
3 2025-09-24 0.08%

Full EPSS history (6 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2024-43378

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
1.4 5.8 [email protected]

Weakness enumeration for CVE-2024-43378

Affected software / configurations for CVE-2024-43378

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2024-43378

cvelogic Threat Intelligence