CVE-2023-43637 is a high-severity (CVSS 7.8) CWE-321 vulnerability in github.com/lf-edge/eve. A fix is available for github.com/lf-edge/eve — see the affected versions and patch details below.
Vault Key Partially Predetermined
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-43637.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
github.com/lf-edge/eveReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Due to the implementation of "deriveVaultKey", prior to version 7.10, the generated vault key would always have the last 16 bytes predetermined to be "arfoobarfoobarfo".
This issue happens because "deriveVaultKey" calls "retrieveCloudKey" (which will always return "foobarfoobarfoobarfoobarfoobarfo" as the key), and then merges the 32byte randomly generated key with this key (by takeing 16bytes from each, see "mergeKeys").
This makes the key a lot weaker.
This issue does not persist in devices that were initialized on/after version 7.10, but devices that were initialized before that and updated to a newer version still have this issue.
Roll an update that enforces the full 32bytes key usage.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/lf-edge/eve | all versions | 0.0.0-20220310190112-c0c966dc31e2go get github.com/lf-edge/eve@v0.0.0-20220310190112-c0c966dc31e2 |
Affected Products
evelfedgeDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/lf-edge/eve, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/lf-edge/eve to 0.0.0-20220310190112-c0c966dc31e2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-43637 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.
Frequently Asked Questions
Is CVE-2023-43637 in your dependencies?
Find it across Go, including transitive dependencies.