XSS in Superpwa Super Progressive Web Apps

CVE-2026-5108

The Super Progressive Web Apps plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the `superpwa_settings[offline_message_txt]` setting in all versions up to, and including, 2.2.43. This is due to insufficient input sanitization and output escaping. The offline message value is stored without sanitization, passed to the frontend via `wp_localize_script()` without escaping, and rendered using `innerHTML` in the JavaScript snackbar component. This makes it possible for authenticated attackers, with Administrator-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user triggers the offline snackbar.

Vulnerability class: XSS (Cross-Site Scripting)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 4.4 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (23.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 24th percentile — 23.9% 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-2026-5108: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-5108?
CVE-2026-5108 is a medium-severity vulnerability in Superpwa Super Progressive Web Apps, classified under Cross-site Scripting. CVSS score: 4.4/10. Published 2026-08-05.
How severe is CVE-2026-5108?
Medium severity. CVSS v3 base score is 4.4 out of 10.