Is CVE-2026-123622 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-123622 being exploited in the wild.

How severe is CVE-2026-123622?

Medium severity, with a CVSS score of 6.1, published 6 November 2026.

Is there a fix for CVE-2026-123622?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-123622 attacked?

It is attacked over the network, in a web application.

Am I affected by CVE-2026-123622?

Check whether you run Webmin Usermin at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-123622: Usermin cross-site scripting in mailbox attachment handling

CVE-2026-123622 · Severity: medium · CVSS 6.1 · Published 2026-11-06

Usermin is a web-based email and system administration interface for end users. A cross-site scripting vulnerability in the mailbox attachment viewer allows attackers to execute arbitrary JavaScript in an authenticated user's browser session by sending a malicious HTML attachment and tricking the user to open it with a crafted link. This could lead to session hijacking, email theft, or other account compromise.

Vendors: Webmin.

Quick answers

Is CVE-2026-123622 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-123622 being exploited in the wild.
How severe is CVE-2026-123622?: Medium severity, with a CVSS score of 6.1, published 6 November 2026.
Which products and versions are affected?: Webmin Usermin through 2.570.
Is there a fix for CVE-2026-123622?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-123622 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2026-123622?: Check whether you run Webmin Usermin at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The vulnerability exists in mailbox/detach.cgi where the type parameter bypasses JavaScript filtering protections. When an attacker supplies type=text/html, the script skips the filter_javascript() call that would normally sanitize HTML content, directly outputting the attachment data. The attack requires the victim to be authenticated in Usermin and to click a malicious link crafted by the attacker.

Affected products

Webmin Usermin through 2.570

Timeline

2026-11-06: disclosed

References

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