CVE-2026-13354: Asset CleanUp: Page Speed Booster <= 1.4.0.5 - Unauthenticated Stored Cross-Site Scripting via Comment Content

Q: Which installations are exposed to exploitation?

Instances running Asset CleanUp: Page Speed Booster version 1.4.0.5 or earlier are exposed only when the combine_loaded_css setting is enabled.

Q: Does exploitation require an authenticated WordPress account or user interaction?

No. An unauthenticated attacker can inject script content, and the script executes when a user later accesses the injected page.

Q: What is the impact if the vulnerability is exploited?

Attackers can store arbitrary web scripts in affected pages. Those scripts run in the browser of users who visit an injected page, with scope changed indicated by the supplied vector.

Published Sep 19, 2026

Updated

The Asset CleanUp: Page Speed Booster plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Comment Content in all versions up to, and including, 1.4.0.5 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This is only exploitable on instances where combineloadedcss has been enabled.

Affected Software

1 affected component

Asset CleanUp Page Speed Booster<=1.4.0.5

Remediation

Recommended actions to resolve this vulnerability, in priority order.

Configuration
Disable combine_loaded_css because the vulnerability is only exploitable when combine_loaded_css has been enabled.
Asset CleanUp: Page Speed Booster (WordPress plugin) combine_loaded_css = disabled

Event History

Sep 19, 2026

CVE Published

via MITRE·02:27 AM

Data Sourced

via MITRE·02:27 AM

DescriptionSeverityWeakness

Frequently Asked Questions

Which installations are exposed to exploitation?

Instances running Asset CleanUp: Page Speed Booster version 1.4.0.5 or earlier are exposed only when the combine_loaded_css setting is enabled.

Does exploitation require an authenticated WordPress account or user interaction?

No. An unauthenticated attacker can inject script content, and the script executes when a user later accesses the injected page.

What is the impact if the vulnerability is exploited?

Attackers can store arbitrary web scripts in affected pages. Those scripts run in the browser of users who visit an injected page, with scope changed indicated by the supplied vector.

CVE-2026-13354: Asset CleanUp: Page Speed Booster <= 1.4.0.5 - Unauthenticated Stored Cross-Site Scripting via Comment Content

Affected Software

Remediation

Event History

Frequently Asked Questions

Which installations are exposed to exploitation?

Does exploitation require an authenticated WordPress account or user interaction?

What is the impact if the vulnerability is exploited?

Company

Resources

Contact

Frequently Asked Questions

Which installations are exposed to exploitation?

Does exploitation require an authenticated WordPress account or user interaction?

What is the impact if the vulnerability is exploited?