CVE-2026-123621

high

Description

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.

References

https://www.vulncheck.com/advisories/usermin-through-2.570-path-traversal-file-write-via-detachall-cgi

https://hackmd.io/@leediay/H144QKY6zl

https://github.com/webmin/usermin/issues/142

https://github.com/webmin/usermin/commit/cb4614e8319e0932b10533a4d5606debf5f40e14

https://github.com/webmin/usermin/blob/2.570/mailbox/detachall.cgi#L43-L51

https://github.com/webmin/usermin

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-118297

Details

Source: Mitre, NVD

Published: 2026-11-06

Updated: 2026-11-12

Risk Information

CVSS v2

Base Score: 10

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

Severity: Critical

CVSS v3

Base Score: 8.8

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Severity: High

CVSS v4

Base Score: 8.6

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Severity: High

EPSS

EPSS: 0.00984