# CVE-2021-20366: Cross-site scripting in Cloud Pak for Applications

> Attackers can inject JavaScript into the IBM Cloud Pak for Applications web interface to steal user credentials and alter functionality.

- **Severity:** Medium 5.4 (`CVSS:3.0/PR:L/UI:R/I:L/AC:L/A:N/S:C/AV:N/C:L/E:H/RC:C/RL:O`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 13 Jul 2021
- **Updated:** 16 Sep 2024
- **Also known as:** GHSA-743v-8938-x3xv

## What is CVE-2021-20366?

CVE-2021-20366 is a medium-severity cross-site scripting vulnerability in IBM Cloud Pak for Applications, published on 13 Jul 2021. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

IBM Cloud Pak for Applications 4.3 is vulnerable to cross-site scripting. This vulnerability allows users to embed arbitrary JavaScript code in the Web UI thus altering the intended functionality potentially leading to credentials disclosure within a trusted session. IBM X-Force ID: 195037.

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

## Which versions are affected by CVE-2021-20366?

It affects 1 product.


Products: Ibm Cloud Pak for Applications.

## How do I fix CVE-2021-20366?

No fix has been published for CVE-2021-20366 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-20366 being exploited?

There is no known exploitation of CVE-2021-20366 in the wild and no public exploit code.

## Other vulnerabilities in IBM Cloud Pak for Applications

- [CVE-2021-20423](https://insights.sbomify.com/CVE-2021-20423/): Privilege escalation in Cloud Pak for Applications (high 8.8)
- [CVE-2021-20422](https://insights.sbomify.com/CVE-2021-20422/): Information disclosure in Cloud Pak for Applications (high 7.5)
- [CVE-2021-20360](https://insights.sbomify.com/CVE-2021-20360/): Weak cryptography in Cloud Pak for Applications (medium 5.9)
- [CVE-2021-20369](https://insights.sbomify.com/CVE-2021-20369/): Weak cryptography in Cloud Pak for Applications (medium 5.9)
- [CVE-2021-20361](https://insights.sbomify.com/CVE-2021-20361/): Cross-site scripting in Cloud Pak for Applications (medium 5.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-20366 and fix it if it is affected.

What it is: CVE-2021-20366 is a medium-severity cross-site scripting vulnerability in IBM Cloud Pak for Applications, published on 13 Jul 2021. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2021-20366 in the wild and no public exploit code.

Affected product: IBM Cloud Pak for Applications. 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-2021-20366/ (Markdown: https://insights.sbomify.com/CVE-2021-20366/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-20366
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-20366
- OSV: https://osv.dev/vulnerability/CVE-2021-20366

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-20366/
Summaries are generated and may contain mistakes; the official description above is the record.