Usermin through 2.570 contains a path traversal vulnerability in mailbox/detachall.cgi that allows remote unauthenticated attackers to…
CVE-2026-123621
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.
Assessment
- CVSS
- 8.6 (v4.0)
- Severity
- High
- Known exploited
- Not listed in CISA KEV
- Exploit availability
- Nothing found in Exploit-DB, Metasploit, Nuclei or public PoC repositories
- Published
- 6 November 2026
- Last updated
- 6 November 2026
- Assigner
- VulnCheck
CVSS vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
At the source
References
- https://github.com/webmin/usermin/issues/142
- https://github.com/webmin/usermin
- https://github.com/webmin/usermin/commit/cb4614e8319e0932b10533a4d5606debf5f40e14
- https://github.com/webmin/usermin/blob/2.570/mailbox/detachall.cgi#L43-L51
- https://hackmd.io/@leediay/H144QKY6zl
- https://www.vulncheck.com/advisories/usermin-through-2.570-path-traversal-file-write-via-detachall-cgi
Community proofs of concept
No community proof of concept yet. If you have one for a published vulnerability and the right to share it, add it below — it will appear here once reviewed.
Submit a proof of concept
Only for publicly disclosed vulnerabilities, and only material from testing you were authorised to perform. This platform does not buy, sell, or broker exploits — see earning from vulnerability research for legitimate bounty programs. Submissions are reviewed before they appear. Text only; do not include live credentials, personal data, or anything targeting systems you are not permitted to test.
Query this programmatically
Agents can read this through the MCP endpoint, or over HTTP:
curl https://cve.zerocrew.in/api/cve/CVE-2026-123621