CVE-2026-87920Network attack vectorHinoki check available

Stored XSS via query-string rewrite of comments

Published Oct 2, 2026 · Updated Oct 2, 2026

Stored XSS in Web Ventures W3 Total Cache 2.10.6 and earlier allows remote attackers to run scripts in visitors' browsers via comments. The output-buffer regex rewrite passes comment-influenced markup to mutate_url(), which removes a question mark and the following text, including an attribute's closing quote. Exploitation requires the Remove query strings from static resources option and a visitor to open an injected page; the resulting script runs in that visitor's browser.

CVSS severity7.2
High
EPSS probability0.24%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Stored XSS in Web Ventures W3 Total Cache 2.10.6 and earlier allows remote attackers to run scripts in visitors' browsers via comments. The output-buffer regex rewrite passes comment-influenced markup to mutate_url(), which removes a question mark and the following text, including an attribute's closing quote. Exploitation requires the Remove query strings from static resources option and a visitor to open an injected page; the resulting script runs in that visitor's browser.

The record

CVE
CVE-2026-87920
Published
Oct 2, 2026
Updated
Oct 2, 2026
Vendor
Web Ventures
Product
W3 Total Cache
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 2, 2026CVE publishedPublication date reported by the CVE source.
  2. Oct 2, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=2.10.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Web Ventures · W3 Total Cacheversion=0 <=2.10.6

Published CVSS scores

7.2Wordfence CNACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007JavaScript

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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