# CVE-2021-29448: Stored DOM XSS in Pi-hole Admin Web Interface

> An attacker with network access to the DNS server can inject malicious scripts into the Pi-hole Admin portal, potentially compromising administrator sessions.

- **Severity:** High 7.6 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H`)
- **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:** 15 Apr 2021
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-cwwf-93p7-73j9

## What is CVE-2021-29448?

CVE-2021-29448 is a high-severity cross-site scripting vulnerability in pi-hole AdminLTE, published on 15 Apr 2021. 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

Pi-hole is a Linux network-level advertisement and Internet tracker blocking application. The Stored XSS exists in the Pi-hole Admin portal, which can be exploited by the malicious actor with the network access to DNS server. See the referenced GitHub security advisory for patch details.

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

## Which versions are affected by CVE-2021-29448?

It affects 3 products.


Products: Pi-Hole Ftldns, Pi-Hole Pi-Hole, Pi-Hole Web Interface.

## How do I fix CVE-2021-29448?

No fix has been published for CVE-2021-29448 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-29448 being exploited?

There is no known exploitation of CVE-2021-29448 in the wild and no public exploit code.

## Other vulnerabilities in pi-hole AdminLTE

- [CVE-2026-35517](https://insights.sbomify.com/CVE-2026-35517/): Pi-hole FTL affected by Remote Code Execution (RCE) via dns.upstreams Newline Injection (high 8.8)
- [CVE-2026-35518](https://insights.sbomify.com/CVE-2026-35518/): Pi-hole FTL affected by Remote Code Execution (RCE) via dns.cnameRecords Newline Injection (high 8.8)
- [CVE-2026-35519](https://insights.sbomify.com/CVE-2026-35519/): Pi-hole FTL affected by Remote Code Execution (RCE) via dns.hostRecord Newline Injection (high 8.8)
- [CVE-2026-35520](https://insights.sbomify.com/CVE-2026-35520/): Pi-hole FTL affected by Remote Code Execution (RCE) via dhcp.leaseTime Newline Injection (high 8.8)
- [CVE-2026-35521](https://insights.sbomify.com/CVE-2026-35521/): Pi-hole FTL affected by Remote Code Execution (RCE) via dhcp.hosts Newline Injection (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-29448 and fix it if it is affected.

What it is: CVE-2021-29448 is a high-severity cross-site scripting vulnerability in pi-hole AdminLTE, published on 15 Apr 2021. 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-2021-29448 in the wild and no public exploit code.

Affected product: pi-hole AdminLTE. 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-2021-29448/ (Markdown: https://insights.sbomify.com/CVE-2021-29448/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-29448
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-29448
- OSV: https://osv.dev/vulnerability/CVE-2021-29448

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-29448/
Summaries are generated and may contain mistakes; the official description above is the record.