# CVE-2026-15604: Toocheke Companion <= 2.10 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'series_bg_color' Post Meta

> Authenticated attackers can inject arbitrary scripts via post meta, leading to code execution or account takeover when admins view the series list.

- **Severity:** Medium 6.4 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 16 Aug 2026
- **Updated:** 18 Aug 2026
- **Also known as:** GHSA-vrrh-33qv-f36q

## What is CVE-2026-15604?

CVE-2026-15604 is a medium-severity cross-site scripting vulnerability in Toocheke Companion, published on 16 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

The Toocheke Companion plugin for WordPress is vulnerable to Stored Cross-Site Scripting in versions up to, and including, 2.10 via the 'series_bg_color' post meta field. This is due to insufficient input sanitization in the toocheke_series_bg_color_save() function (which stores the raw $_POST value in post meta) and insufficient output escaping in the series admin column rendering (where the stored value is concatenated into a style attribute without esc_attr()). This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user, such as an administrator, accesses the series list table in the admin dashboard.

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

## Which versions are affected by CVE-2026-15604?


## How do I fix CVE-2026-15604?

No fix has been published for CVE-2026-15604 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-15604 being exploited?

There is no known exploitation of CVE-2026-15604 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-15604 and fix it if it is affected.

What it is: CVE-2026-15604 is a medium-severity cross-site scripting vulnerability in Toocheke Companion, published on 16 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-15604 in the wild and no public exploit code.

Affected product: Toocheke Companion. 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-2026-15604/ (Markdown: https://insights.sbomify.com/CVE-2026-15604/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-15604
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-15604
- OSV: https://osv.dev/vulnerability/CVE-2026-15604

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-15604/
Summaries are generated and may contain mistakes; the official description above is the record.