---
id: CVE-2026-123621
title: Usermin through 2.570 Path Traversal File Write via detachall.cgi
summary: >-
  Usermin through 2.570 contains a path traversal vulnerability in
  mailbox/detachall.cgi that allows remote unauthenticated attackers to write
  files outside the temporary directory via unsanitized attachment filenames.
  Attackers can email …
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H'
cvssSource: cna
cwe:
  - CWE-22
vendor: webmin
product: usermin
affected:
  - usermin <= 2.570
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-11-06T17:24:19.100245Z'
exploitAvailable: true
published: '2026-11-06'
updated: '2026-11-06'
sourceUpdated: '2026-11-06T17:26:03.502Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-123621'
references:
  - url: 'https://github.com/webmin/usermin/issues/142'
    label: 'GitHub Issue #142'
  - url: 'https://github.com/webmin/usermin'
  - url: >-
      https://github.com/webmin/usermin/commit/cb4614e8319e0932b10533a4d5606debf5f40e14
    label: Fix commit cb4614e
  - url: 'https://github.com/webmin/usermin/blob/2.570/mailbox/detachall.cgi#L43-L51'
    label: detachall.cgi attachment write
  - url: 'https://hackmd.io/@leediay/H144QKY6zl'
    label: Researcher write-up
  - url: >-
      https://www.vulncheck.com/advisories/usermin-through-2.570-path-traversal-file-write-via-detachall-cgi
    label: >-
      VulnCheck Advisory: Usermin through 2.570 Path Traversal File Write via
      detachall.cgi
tags:
  - cve.org
  - exploit-available
ingestedAt: '2026-11-06T15:54:04.079Z'
epss: 0.00984
epssPercentile: 0.62549
---

## Overview

Usermin through 2.570 contains a path traversal vulnerability in mailbox/detachall.cgi that allows remote unauthenticated attackers to write files outside the temporary directory via unsanitized attachment filenames. Attackers can email attachments with ../ sequences in filenames, and when the recipient downloads all attachments, files like ~/.forward are overwritten, enabling command execution.

## Affected

- `usermin <= 2.570`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.