What is CVE-2015-9439?

CVE-2015-9439 is a medium-severity vulnerability in Addthis, classified under Cross-site Scripting. CVSS score: 4.8/10. Published 2019-09-26.

How severe is CVE-2015-9439?

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

Is CVE-2015-9439 known to be exploited?

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

XSS in Addthis

CVE-2015-9439

The addthis plugin before 5.0.13 for WordPress has CSRF with resultant XSS via the wp-admin/options-general.php?page=addthis_social_widget pubid parameter.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2019-09-26 · 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: 0.010 (60.8th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 61st percentile — 60.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.010 · newest: 0.010 · change: 0.000

Affected products

Addthis

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

Public proof-of-concept exploits

20142995/nuclei-templates

References

wpvulndb.com/vulnerabilities/8246 (Third Party Advisory)
wordpress.org/plugins/addthis/ (Product, Release Notes)
blog.cinu.pl/2015/11/php-static-code-analysis-vs-top-1000-wordpress-plugins.html (Third Party Advisory)

Frequently asked questions

What is CVE-2015-9439?: CVE-2015-9439 is a medium-severity vulnerability in Addthis, classified under Cross-site Scripting. CVSS score: 4.8/10. Published 2019-09-26.
How severe is CVE-2015-9439?: Medium severity. CVSS v3 base score is 4.8 out of 10.
Is CVE-2015-9439 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.