CVE-2026-66358Network attack vector

Script execution via undisclosed XSS

Published Aug 19, 2026 · Updated Aug 20, 2026

Cross-site scripting in Extra Innovation acmailer allows remote attackers to execute arbitrary script in a user's browser via unspecified vectors. JVN and the vendor release identify an XSS fix, but neither source names the affected page, parameter, or output path that renders untrusted input without neutralization. Exploitation requires a user to load attacker-controlled content in the vulnerable web interface; published impact is limited to script execution in that browser context.

CVSS severity5.1
Medium
EPSS probability0.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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 Extra Innovation acmailer allows remote attackers to execute arbitrary script in a user's browser via unspecified vectors. JVN and the vendor release identify an XSS fix, but neither source names the affected page, parameter, or output path that renders untrusted input without neutralization. Exploitation requires a user to load attacker-controlled content in the vulnerable web interface; published impact is limited to script execution in that browser context.

The record

CVE
CVE-2026-66358
Published
Aug 19, 2026
Updated
Aug 20, 2026
Vendor
Extra Innovation Inc.
Product
acmailer DB
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 20, 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=0 <1.2.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Extra Innovation Inc. · acmailer DBversion=0 <1.2.2
Extra Innovation Inc. · acmailer CGIversion=0 <4.1.2

Published CVSS scores

5.1JPCERT/CCCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
6.1JPCERT/CCCVSS:3.0/AV:N/AC:L/PR:N/UI:R/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.

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

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 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.

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