What is CVE-2023-43309?

CVE-2023-43309 is a medium-severity vulnerability in Webmin, classified under Cross-site Scripting. CVSS score: 4.8/10. Published 2023-09-21.

How severe is CVE-2023-43309?

Medium severity. CVSS v3 base score is 4.8 out of 10.

XSS in Webmin

CVE-2023-43309

There is a stored cross-site scripting (XSS) vulnerability in Webmin 2.002 and below via the Cluster Cron Job tab Input field, which allows attackers to run malicious scripts by injecting a specially crafted payload.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2023-09-21 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 4.8 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.005 (37.1th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 37th percentile — 37.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.004 · newest: 0.005 · change: +0.001

Affected products

Webmin

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

github.com/TishaManandhar/Webmin_xss_POC/blob/main/XSS (Exploit, Third Party Advisory)

Frequently asked questions

What is CVE-2023-43309?: CVE-2023-43309 is a medium-severity vulnerability in Webmin, classified under Cross-site Scripting. CVSS score: 4.8/10. Published 2023-09-21.
How severe is CVE-2023-43309?: Medium severity. CVSS v3 base score is 4.8 out of 10.