# CVE-2026-107743: Mapster WP Maps <= 2.0.5 - Unauthenticated Stored Cross-Site Scripting via 'config.loading.background' Parameter


- **Severity:** High 7.2 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Fix available:** No
- **Published:** 29 Oct 2026
- **Updated:** 29 Oct 2026
- **Also known as:** GHSA-4r6v-cgvq-4mgw

## What is CVE-2026-107743?

CVE-2026-107743 is a high-severity vulnerability in Mapster WP Maps, published on 29 Oct 2026. 

### Official description

The Mapster WP Maps plugin for WordPress is vulnerable to Stored Cross-Site Scripting in versions up to, and including, 2.0.5. This is due to the /wp-json/mapster-wp-maps/save-mapmaker REST route being registered with a permission_callback that unconditionally returns true (no capability check, no nonce), together with the mapster_write_config_to_acf() helper only sanitizing string config values with sanitize_text_field() — which strips HTML tags but leaves quote characters intact — and the mapster_wp_map shortcode renderer in mapster_wordpress_maps_shortcode_display() concatenating the stored loading_background_color value into a single-quoted inline style attribute without esc_attr(). This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

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

## Which versions are affected by CVE-2026-107743?


## How do I fix CVE-2026-107743?

No fix has been published for CVE-2026-107743 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-107743 being exploited?

There is no known exploitation of CVE-2026-107743 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-107743 and fix it if it is affected.

What it is: CVE-2026-107743 is a high-severity vulnerability in Mapster WP Maps, published on 29 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-107743 in the wild and no public exploit code.

Affected product: Mapster WP Maps. 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-2026-107743/ (Markdown: https://insights.sbomify.com/CVE-2026-107743/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-107743
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-107743
- OSV: https://osv.dev/vulnerability/CVE-2026-107743

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-107743/
Summaries are generated and may contain mistakes; the official description above is the record.