CVE-2023-39950 — efibootguard is a simple UEFI boot loader with support for safely switching betw
efibootguard is a simple UEFI boot loader with support for safely switching between current and updated partition sets. Insufficient or missing validation and sanitization of input from untrustworthy bootloader environment files can cause crashes and probably also code injections
Published
2023-08-14T20:17:29.931Z
Last modified
2024-10-01T18:24:16.409Z
CVSS vector
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:L
01What is this vulnerability?
efibootguard is a simple UEFI boot loader with support for safely switching between current and updated partition sets. Insufficient or missing validation and sanitization of input from untrustworthy bootloader environment files can cause crashes and probably also code injections into `bg_setenv`) or programs using `libebgenv`. This is triggered when the affected components try to modify a…
02Affected products
| Vendor | Product | Versions |
|---|
| siemens | efibootguard | < 0.15 |
03Active exploitation status
Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.
04Recommended remediation
- Patch to a fixed version listed in the vendor advisory (see references below).
- Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
- Hunt historical logs for exploitation indicators — see Detection signatures below.
05Technical details
For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.
06Detection signatures
Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection in your stack of choice:
Open in Sigma generator →
07Related CVEs
No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.
08Timeline
- Published: 2023-08-14T20:17:29.931Z
- Last modified: 2024-10-01T18:24:16.409Z
09References
- github.com — https://github.com/siemens/efibootguard/security/advisories/GHSA-j6pp-7g99-24m7
- github.com — https://github.com/siemens/efibootguard/blob/master/docs/API.md
- github.com — https://github.com/siemens/efibootguard/blob/master/docs/TOOLS.md
- github.com — https://github.com/siemens/efibootguard/blob/master/docs/TOOLS.md#setting-user-v…
- github.com — https://github.com/siemens/efibootguard/tags
Want this in your SOAR or SIEM?
SARA's API returns EPSS, CVSS, KEV, and an analyst-grade summary in one call.
Read the API reference →