# CVE-2020-28707: Cross-site scripting in n/a

> Cross-site scripting vulnerability in Stockdio Historical Chart plugin allows attackers to execute arbitrary JavaScript via unvalidated postMessage events.

- **Severity:** Medium 6.1 (`CVSS:3.1/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:** 19 Jan 2021
- **Updated:** 9 Jul 2026
- **Also known as:** GHSA-8rwm-vgc4-5hgx

## What is CVE-2020-28707?

CVE-2020-28707 is a medium-severity cross-site scripting vulnerability in n/a, published on 19 Jan 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

The Stockdio Historical Chart plugin before 2.8.1 for WordPress is affected by Cross Site Scripting (XSS) via stockdio_chart_historical-wp.js in wp-content/plugins/stockdio-historical-chart/assets/ because the origin of a postMessage() event is not validated. The stockdio_eventer function listens for any postMessage event. After a message event is sent to the application, this function sets the "e" variable as the event and checks that the types of the data and data.method are not undefined (empty) before proceeding to eval the data.method received from the postMessage. However, on a different website. JavaScript code can call window.open for the vulnerable WordPress instance and do a postMessage(msg,'*') for that object.

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

## Which versions are affected by CVE-2020-28707?

It affects 1 product.


Products: Stockdio Stockdio Historical Chart.

## How do I fix CVE-2020-28707?

No fix has been published for CVE-2020-28707 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-28707 being exploited?

There is no known exploitation of CVE-2020-28707 in the wild and no public exploit code.

Public exploit code:

- Hands-on Learn SecByte CTF labs covering Venus reconnaissance, service discovery, cookies, PHP investigation, secrets, root-focused challenges, and CVE-2020-28707 Stockdio Historical Chart XSS. (github_poc): https://github.com/sifatnotes/Learn-SecByte-Venus-Rips-Recon-PHP-CVE-CTF-Labs

## Other vulnerabilities in n/a

- [CVE-2024-13349](https://insights.sbomify.com/CVE-2024-13349/): Stockdio Historical Chart <= 2.8.18 - Authenticated (Contributor+) Stored Cross-Site Scripting (medium 6.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-28707 and fix it if it is affected.

What it is: CVE-2020-28707 is a medium-severity cross-site scripting vulnerability in n/a, published on 19 Jan 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-2020-28707 in the wild and no public exploit code.

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-2020-28707/ (Markdown: https://insights.sbomify.com/CVE-2020-28707/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-28707
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-28707
- OSV: https://osv.dev/vulnerability/CVE-2020-28707

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From sbomify Insights: https://insights.sbomify.com/CVE-2020-28707/
Summaries are generated and may contain mistakes; the official description above is the record.