# CVE-2019-12581: Cross-site scripting in n/a

> Remote attackers can inject arbitrary web script via the err_msg parameter in Zyxel firewall devices, potentially compromising user sessions.

- **Severity:** Medium 6.1 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 27 Jun 2019
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-5f8r-3j92-cp9m

## What is CVE-2019-12581?

CVE-2019-12581 is a medium-severity cross-site scripting vulnerability in n/a, published on 27 Jun 2019. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

A reflective Cross-site scripting (XSS) vulnerability in the free_time_failed.cgi CGI program in selected Zyxel ZyWall, USG, and UAG devices allows remote attackers to inject arbitrary web script or HTML via the err_msg parameter.

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

## Which versions are affected by CVE-2019-12581?

It affects 9 products.


Products: Zyxel Uag2100 Firmware, Zyxel Uag4100 Firmware, Zyxel Uag5100 Firmware, Zyxel Usg1100 Firmware, Zyxel Usg110 Firmware, Zyxel Usg1900 Firmware, Zyxel Usg210 Firmware, Zyxel Usg2200-Vpn Firmware, Zyxel Usg310 Firmware.

## How do I fix CVE-2019-12581?

No fix has been published for CVE-2019-12581 yet. Limit exposure of the affected software until one is available.

## Is CVE-2019-12581 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2019-12581 exists.

Public exploit code:

- Zyxel ZyWal/USG/UAG Devices - Cross-Site Scripting (nuclei): http/cves/2019/CVE-2019-12581.yaml

## Other vulnerabilities in n/a

- [CVE-2019-12583](https://insights.sbomify.com/CVE-2019-12583/): Missing authorization in n/a (critical 9.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-12581 and fix it if it is affected.

What it is: CVE-2019-12581 is a medium-severity cross-site scripting vulnerability in n/a, published on 27 Jun 2019. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2019-12581 exists.

Affected product: n/a. 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-2019-12581/ (Markdown: https://insights.sbomify.com/CVE-2019-12581/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-12581
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-12581
- OSV: https://osv.dev/vulnerability/CVE-2019-12581

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-12581/
Summaries are generated and may contain mistakes; the official description above is the record.