CVE-2026-66640Network attack vectorHinoki check available

Contributor XSS via undisclosed mechanism

Published Aug 18, 2026 · Updated Aug 18, 2026

Cross-site scripting in Login With Ajax 4.5.1 and earlier allows remote authenticated users to execute script in visitors' browsers. Patchstack discloses contributor-level reachability but not the vulnerable parameter, output sink, or whether the payload is stored or reflected. Exploitation therefore requires contributor access and a victim page view under the published CVSS vector, while the precise plugin feature and data exposure remain undisclosed.

CVSS severity6.5
Medium
EPSS probability0.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Cross-site scripting in Login With Ajax 4.5.1 and earlier allows remote authenticated users to execute script in visitors' browsers. Patchstack discloses contributor-level reachability but not the vulnerable parameter, output sink, or whether the payload is stored or reflected. Exploitation therefore requires contributor access and a victim page view under the published CVSS vector, while the precise plugin feature and data exposure remain undisclosed.

The record

CVE
CVE-2026-66640
Published
Aug 18, 2026
Updated
Aug 18, 2026
Vendor
Marcus Sykes
Product
Login With Ajax
Classifications
CWE-79
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 18, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 18, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=n/a <=4.5.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Marcus Sykes · Login With Ajaxversion=n/a <=4.5.1

Published CVSS scores

6.5PatchstackCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L

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.

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

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

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

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo