CVE-2026-49103Public exploitNetwork attack vector

Root command execution via attachment filename traversal

Published May 27, 2026 · Updated May 27, 2026

Path traversal in Webmin before 2.640 allows remote attackers to execute commands as root through a crafted email attachment filename. mailboxes/detachall.cgi joins the attachment filename to its temporary directory without stripping directory segments before open_tempfile writes the data. The sender needs a valid address for a user with Read User Email access, and that user must select Download all attachments.

CVSS severity9.4
Critical
EPSS probability0.40%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Path traversal in Webmin before 2.640 allows remote attackers to execute commands as root through a crafted email attachment filename. mailboxes/detachall.cgi joins the attachment filename to its temporary directory without stripping directory segments before open_tempfile writes the data. The sender needs a valid address for a user with Read User Email access, and that user must select Download all attachments.

The record

CVE
CVE-2026-49103
Published
May 27, 2026
Updated
May 27, 2026
Vendor
Webmin
Product
Webmin
Classifications
CWE-24, T1204.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 27, 2026CVE publishedPublication date reported by the CVE source.
  2. May 27, 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 <2.640

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Webmin · Webminversion=0 <2.640

Published CVSS scores

9.4MITRECVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

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.

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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 exploitPublished

Weakness, pattern, technique

CWE-24Path Traversal: '../filedir'
T1204.002Malicious File

Public exploit references

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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