CVE-2026-22678Network attack vector

Administrator-browser script execution via unescaped template description

Published May 21, 2026 · Updated May 21, 2026

Stored XSS in Webmin before 2.641 allows remote authenticated users to execute JavaScript in an administrator's browser. The save_tmpl.cgi handler stores an unsanitized email-template description, and list_tmpls.cgi inserts that value into HTML without output encoding. Exploitation requires permission to create notification email templates and an administrator to view the stored template, exposing that administrator's Webmin session to attacker-controlled script actions.

CVSS severity5.1
Medium
EPSS probability0.22%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in Webmin before 2.641 allows remote authenticated users to execute JavaScript in an administrator's browser. The save_tmpl.cgi handler stores an unsanitized email-template description, and list_tmpls.cgi inserts that value into HTML without output encoding. Exploitation requires permission to create notification email templates and an administrator to view the stored template, exposing that administrator's Webmin session to attacker-controlled script actions.

The record

CVE
CVE-2026-22678
Published
May 21, 2026
Updated
May 21, 2026
Vendor
Webmin
Product
Webmin
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 21, 2026CVE publishedPublication date reported by the CVE source.
  2. May 21, 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 <2.641

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Webmin · Webminversion=0 <2.641

Published CVSS scores

5.1VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
5.4VulnCheckCVSS:3.1/AV:N/AC:L/PR:L/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 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')
T1059.007Command and Scripting Interpreter: JavaScript/JScript

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

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Your stack

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