CVE-2026-78438

W3 Total Cache <= 2.10.5 - Unauthenticated Stored Cross-Site Scripting via LazyLoad Background Mutator

HIGH
7.2
CVSS Score
Published: September 5, 2026 at 06:37 AM UTC
Updated: September 8, 2026 at 01:31 PM UTC
1 product affected across 1 vendorW3 Total Cache

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Severity
HIGH7.2
Exploit prediction
EPSS 0.5%
SSVC
No known exploit

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 malicious comment to be approved by a moderator before execution is triggered.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

60%
v ≤ 2.10.5

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.2HIGHWordfence
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-79

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