# CVE-2023-28800: Output encoding missing in redrurl parameter

> Attackers can execute XSS via the redirect URL parameter in the admin login interface, potentially compromising administrator accounts.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/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:** 22 Jun 2023
- **Updated:** 6 Dec 2024
- **Also known as:** GHSA-crh5-rq78-8m4h

## What is CVE-2023-28800?

CVE-2023-28800 is a high-severity cross-site scripting vulnerability in Zscaler Client Connector, published on 22 Jun 2023. 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

When using local accounts for administration, the redirect url parameter was not encoded correctly, allowing for an XSS attack providing admin login.

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

## Which versions are affected by CVE-2023-28800?

It affects 1 product.


Products: Zscaler Client Connector.

## How do I fix CVE-2023-28800?

No fix has been published for CVE-2023-28800 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-28800 being exploited?

There is no known exploitation of CVE-2023-28800 in the wild and no public exploit code.

## Other vulnerabilities in Zscaler Client Connector

- [CVE-2020-11633](https://insights.sbomify.com/CVE-2020-11633/): Memory corruption in n/a (critical 9.8)
- [CVE-2024-23463](https://insights.sbomify.com/CVE-2024-23463/): Anti-Tampering bypass via Repair App functionality (high 8.8)
- [CVE-2023-28804](https://insights.sbomify.com/CVE-2023-28804/): Linux ZCC allows unsigned updates, allowing elevated Code Execution (high 8.2)
- [CVE-2023-28799](https://insights.sbomify.com/CVE-2023-28799/): Open redirect in Client Connector (high 8.2)
- [CVE-2024-23456](https://insights.sbomify.com/CVE-2024-23456/): Signature validation issue leads to Anti-Tampering bypass (high 7.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-28800 and fix it if it is affected.

What it is: CVE-2023-28800 is a high-severity cross-site scripting vulnerability in Zscaler Client Connector, published on 22 Jun 2023. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2023-28800 in the wild and no public exploit code.

Affected product: Zscaler Client Connector. 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-2023-28800/ (Markdown: https://insights.sbomify.com/CVE-2023-28800/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-28800
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-28800
- OSV: https://osv.dev/vulnerability/CVE-2023-28800

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-28800/
Summaries are generated and may contain mistakes; the official description above is the record.