CVE-2026-78471

Status: DeferredMedium (5.4)—

The Autoptimize plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Comment Author Name in all versions up to, and including, 3.1.15.1 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. Exploitation requires an administrator to have enabled Autoptimize's 'Lazy-load images?' option, the w3-total-cache/w3-total-cache.php file to be present on disk with the plugin disabled, a class named Minify_HTML to be loaded into scope by another plugin, and the malicious comment to be approved by a moderator before the payload renders.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N
Base score: 5.4

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.22%
Percentile among all scored CVEs: 12
Score date: 10/6/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1190 Exploit Public-Facing Applicationinitial access60 %
Primary impactT1059.007 JavaScriptexecution55 %

Inferred by deterministic rules from the CVSS vector and CWE. Indicative only.

🛡️ ATT&CK mitigations that cover these techniques

Vulnerability Scanning Restrict Web-Based Content Privileged Account Management Network Segmentation Limit Access to Resource Over Network Filter Network Traffic

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Autoptimize — Autoptimize^AI

CWEs

CWE-79

References

Raw JSON (NVD)

Show

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  "published": "2026-10-02T06:16:41.240",
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  "lastModified": "2026-10-03T16:16:38.587",
  "sourceIdentifier": "security@wordfence.com"
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