7.2

CVE-2026-78438: boldgrid w3_total_cache Cross-site Scripting

CVSS: 7.2v3.1HighDeferred
Published 05-09-2026Last modified 07-09-2026
Open JSON

Vulnerability summary

CVE-2026-78438 is a high (CVSS 7.2) Cross-site Scripting vulnerability in boldgrid w3_total_cache. EPSS estimates a 0.50% chance of exploitation in the next 30 days, higher than 41.6% of scored vulnerabilities.

Overall risk
29/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.2/10
010
High · v3.1 (CVE.org)
EPSS score
0.50%
0%100%
Low · +0.21 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 05-09-2026
    PublishedVulnerability first disclosed.
  2. 07-09-2026
    Last modifiedVulnerability information updated.

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.

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.50%

Chance of exploitation in the next 30 days

Percentile

42%

Versus all other CVEs

30-day change

+0.21 pp

From 0.29% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.50%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Boldgrid1 product
Wordpress1 product
  • w3-total-cache≤ 2.10.5 (fixed in 2.10.6)

2 vendors · 2 products

References

9 links