Skip to main content
HIGH

CVE-2026-78438

CVSS v3

7.2

HIGH

EPSS Score

0.5 %

exploit probability, as of 2026-09-28

CISA KEV

No

known exploited

Exploitation

—

SSVC status

Description

The W3 Total Cache plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Comment Content via LazyLoad Background Mutator in all versions up to, and including, 2.10.5 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 requires the "Lazy Load Images" feature with "Process background images" to be enabled, and the ma

Technical details

Published
2026-09-05
Last Modified
2026-09-05

Frequently asked questions

What is CVE-2026-78438?

The W3 Total Cache plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Comment Content via LazyLoad Background Mutator in all versions up to, and including, 2.10.5 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 requires the "Lazy Load Images" feature with "Process background images" to be enabled, and the ma

Is CVE-2026-78438 actively exploited?

Active exploitation of CVE-2026-78438 has not been confirmed. Its EPSS score was 0.5% on 2026-09-28, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-78438?

CVE-2026-78438 has a CVSS v3 base score of 7.2 (HIGH severity).

Is CVE-2026-78438 affecting your environment?

Use isMalicious to check if any of your IPs or domains are associated with this vulnerability's IOCs.

Check an IPSearch CVEsSIEM & TIP integrations

No credit card required · 500 free checks/month · Free API key

Other 2026 vulnerabilities worth triaging

Ranked by exploit probability (EPSS).

Back to CVE Database