# CVE-2026-84793: Craft CMS 5.0.0-RC1 before 5.10.11 Stored XSS via site name

> Administrators can inject JavaScript into the site name field, leading to stored XSS execution for other users viewing control panel settings.

- **Severity:** Medium 4.8 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 2 Sep 2026
- **Updated:** 2 Sep 2026
- **Also known as:** GHSA-5fjj-496j-2qqf, GHSA-wf9j-59pf-vfvj

## What is CVE-2026-84793?

CVE-2026-84793 is a medium-severity cross-site scripting vulnerability in craftcms cms, published on 2 Sep 2026. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.

### Official description

Craft CMS versions from 5.0.0-RC1 before 5.10.11 contain a stored cross-site scripting vulnerability in the site name field that fails to sanitize input. Administrators can inject arbitrary JavaScript payloads in the site name that execute when other users view the control panel settings pages.

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

## Which versions are affected by CVE-2026-84793?


## How do I fix CVE-2026-84793?

No fix has been published for CVE-2026-84793 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-84793 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-84793 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-84793 and fix it if it is affected.

What it is: CVE-2026-84793 is a medium-severity cross-site scripting vulnerability in craftcms cms, published on 2 Sep 2026. An attacker needs administrator access to exploit it, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-84793 exists.

Affected product: craftcms cms. 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-2026-84793/ (Markdown: https://insights.sbomify.com/CVE-2026-84793/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-84793
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-84793
- OSV: https://osv.dev/vulnerability/CVE-2026-84793

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-84793/
Summaries are generated and may contain mistakes; the official description above is the record.