XSS in Os4ed Opensis

CVE-2021-40542

Opensis-Classic Version 8.0 is affected by cross-site scripting (XSS). An unauthenticated user can inject and execute JavaScript code through the link_url parameter in Ajax_url_encode.php.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.032 (87.8th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 88th percentile — 87.8% 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-2021-40542: held from 0.032 to 0.032.

EPSS over last 30 days · oldest: 0.032 · newest: 0.032 · change: 0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-40542?
CVE-2021-40542 is a medium-severity vulnerability in Os4ed Opensis, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2021-10-11.
How severe is CVE-2021-40542?
Medium severity. CVSS v3 base score is 6.1 out of 10.
Is CVE-2021-40542 known to be exploited?
3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.