CVE-2026-56021Network attack vector

Unauthenticated file disclosure via unanchored path regex

Published Jun 18, 2026 · Updated Jun 18, 2026

Information disclosure in Webmin allows remote attackers to read .conf files from module directories through crafted HTTP requests. The request-path validation applies a bypassable, unanchored regular expression to module-local configuration filenames instead of enforcing the intended boundary. No authentication or user interaction is required; disclosure is limited to files ending in .conf under Webmin module directories.

CVSS severity6.9
Medium
EPSS probability0.48%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Webmin allows remote attackers to read .conf files from module directories through crafted HTTP requests. The request-path validation applies a bypassable, unanchored regular expression to module-local configuration filenames instead of enforcing the intended boundary. No authentication or user interaction is required; disclosure is limited to files ending in .conf under Webmin module directories.

The record

CVE
CVE-2026-56021
Published
Jun 18, 2026
Updated
Jun 18, 2026
Vendor
Webmin
Product
Webmin
Classifications
CWE-185, CWE-777, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 18, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 18, 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=*

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Webmin · Webminversion=*

Published CVSS scores

6.9CISACVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
5.3CISACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/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-185Incorrect Regular Expression
CWE-777Regular Expression without Anchors
T1190Exploit Public-Facing Application

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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