# CVE-2026-123622: Usermin through 2.570 XSS via mailbox detach.cgi type Parameter


- **Severity:** Medium 5.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N`)
- **Exploited in the wild:** Not known
- **Fix available:** No
- **Published:** 6 Nov 2026
- **Updated:** 11 Nov 2026
- **Also known as:** GHSA-pqrp-xhqp-wc9w

## What is CVE-2026-123622?

CVE-2026-123622 is a medium-severity vulnerability in webmin usermin, published on 6 Nov 2026. 

### Official description

Usermin through 2.570 contains a cross-site scripting vulnerability in mailbox/detach.cgi that allows remote attackers to execute script by supplying an arbitrary type parameter that bypasses JavaScript filtering. Attackers can email an HTML attachment containing script and lure recipients to a detach.cgi link with type=text/html to run script in the victim's authenticated Usermin session.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation)

## Which versions are affected by CVE-2026-123622?


## How do I fix CVE-2026-123622?

No fix has been published for CVE-2026-123622 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-123622 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-123622 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-123622 and fix it if it is affected.

What it is: CVE-2026-123622 is a medium-severity vulnerability in webmin usermin, published on 6 Nov 2026. 
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-123622 exists.

Affected product: webmin usermin. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-123622/ (Markdown: https://insights.sbomify.com/CVE-2026-123622/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-123622
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-123622
- OSV: https://osv.dev/vulnerability/CVE-2026-123622

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-123622/
Summaries are generated and may contain mistakes; the official description above is the record.