XSS in Tstachl WordPress Paypal Donation

CVE-2026-4072

The WordPress PayPal Donation plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'donate' shortcode in all versions up to, and including, 1.01. This is due to insufficient input sanitization and output escaping on user-supplied shortcode attributes such as 'amount', 'email', 'title', 'return_url', 'cancel_url', 'ccode', and 'image'. The wordpress_paypal_donation_create() function uses extract(shortcode_atts(...)) to process shortcode attributes and then directly interpolates these values into HTML output within single-quoted attribute values without any escaping. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (24.3th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 24th percentile — 24.3% 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-2026-4072: held from 0.002 to 0.003.

EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-4072?
CVE-2026-4072 is a medium-severity vulnerability in Tstachl WordPress Paypal Donation, classified under Cross-site Scripting. CVSS score: 6.4/10. Published 2026-03-21.
How severe is CVE-2026-4072?
Medium severity. CVSS v3 base score is 6.4 out of 10.