Path Traversal in Sma Boy 3.0

CVE-2021-4459

An authorized remote attacker can access files and directories outside the intended web root, potentially exposing sensitive system information of the affected Sunny Boy devices.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.007 (50.1th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 50th percentile — 50.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2021-4459: held from 0.007 to 0.007.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: +0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-4459?
CVE-2021-4459 is a medium-severity vulnerability in Sma Boy 3.0, classified under Relative Path Traversal. CVSS score: 6.5/10. Published 2025-08-27.
How severe is CVE-2021-4459?
Medium severity. CVSS v3 base score is 6.5 out of 10.