# CVE-2026-21664: Cross-site scripting in Revive Adserver

> Reflected XSS in Revive Adserver allows attackers to execute malicious scripts in an administrator's browser via a crafted URL.

- **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:** 20 Jan 2026
- **Updated:** 21 Jan 2026
- **Also known as:** GHSA-982f-qxrw-6prp

## What is CVE-2026-21664?

CVE-2026-21664 is a medium-severity cross-site scripting vulnerability in Revive Adserver, published on 20 Jan 2026. 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

HackerOne community member Huynh Pham Thanh Luc (nigh7c0r3) has reported a reflected XSS vulnerability in the afr.php delivery script of Revive Adserver. An attacker can craft a specific URL that includes an HTML payload in a parameter. If a logged in administrator visits the URL, the HTML is sent to the browser and malicious scripts would be executed.

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

## Which versions are affected by CVE-2026-21664?

It affects 1 product.


Products: Aquaplatform Revive Adserver.

## How do I fix CVE-2026-21664?

No fix has been published for CVE-2026-21664 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-21664 being exploited?

There is no known exploitation of CVE-2026-21664 in the wild and no public exploit code.

## Other vulnerabilities in Revive Adserver

- [CVE-2026-21641](https://insights.sbomify.com/CVE-2026-21641/): Missing authorization in Revive Adserver (high 7.1)
- [CVE-2025-55126](https://insights.sbomify.com/CVE-2025-55126/): Cross-site scripting in Revive Adserver (medium 6.5)
- [CVE-2025-55128](https://insights.sbomify.com/CVE-2025-55128/): Denial of service in Revive Adserver (medium 6.5)
- [CVE-2026-21642](https://insights.sbomify.com/CVE-2026-21642/): Cross-site scripting in Revive Adserver (medium 6.1)
- [CVE-2026-21663](https://insights.sbomify.com/CVE-2026-21663/): Cross-site scripting in Revive Adserver (medium 6.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-21664 and fix it if it is affected.

What it is: CVE-2026-21664 is a medium-severity cross-site scripting vulnerability in Revive Adserver, published on 20 Jan 2026. 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-2026-21664 in the wild and no public exploit code.

Affected product: Revive Adserver. 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-2026-21664/ (Markdown: https://insights.sbomify.com/CVE-2026-21664/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-21664
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-21664
- OSV: https://osv.dev/vulnerability/CVE-2026-21664

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-21664/
Summaries are generated and may contain mistakes; the official description above is the record.