What is CVE-2023-5560?

CVE-2023-5560 is a medium-severity vulnerability in Lesterchan Wp-Useronline, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2023-11-27.

How severe is CVE-2023-5560?

Medium severity. CVSS v3 base score is 6.1 out of 10.

Is CVE-2023-5560 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

XSS in Lesterchan Wp-Useronline

CVE-2023-5560

The WP-UserOnline WordPress plugin before 2.88.3 does not sanitise and escape the X-Forwarded-For header before outputting its content on the page, which allows unauthenticated users to perform Cross-Site Scripting attacks.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2023-11-27 · last modified 2026-06-17.

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: 0.005 (41.2th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 41st percentile — 41.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Lesterchan Wp-Useronline
Wp-Useronline — versions 0

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

Public proof-of-concept exploits

20142995/nuclei-templates

References

wpscan.com/vulnerability/55d23184-fc5a-4090-b079-142407b59b05 (Exploit, technical-description, Third Party Advisory, exploit, vdb-entry)

Frequently asked questions

What is CVE-2023-5560?: CVE-2023-5560 is a medium-severity vulnerability in Lesterchan Wp-Useronline, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2023-11-27.
How severe is CVE-2023-5560?: Medium severity. CVSS v3 base score is 6.1 out of 10.
Is CVE-2023-5560 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.