# CVE-2026-64628: Grav Stored Cross-Site Scripting via Shortcode Attribute Handlers

> Attackers with admin.pages permission can inject malicious JavaScript via shortcode attributes, leading to session hijacking and admin nonce theft.

- **Severity:** Medium 5.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N`)
- **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:** 21 Jul 2026
- **Updated:** 23 Jul 2026
- **Also known as:** GHSA-r7ww-mw2x-mj59

## What is CVE-2026-64628?

CVE-2026-64628 is a medium-severity cross-site scripting vulnerability in getgrav grav, published on 21 Jul 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

Grav contains a stored cross-site scripting vulnerability in shortcode-core attribute handlers where the XSS detection scan only matches payloads containing literal angle brackets, allowing shortcode parameters to bypass validation. Attackers with admin.pages permission can inject malicious JavaScript through shortcode attributes that execute in any viewer's browser, including administrators, enabling session hijacking via admin nonce theft.

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

## Which versions are affected by CVE-2026-64628?


## How do I fix CVE-2026-64628?

No fix has been published for CVE-2026-64628 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-64628 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-64628 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-64628 and fix it if it is affected.

What it is: CVE-2026-64628 is a medium-severity cross-site scripting vulnerability in getgrav grav, published on 21 Jul 2026. Any signed-in user can exploit it over the network, 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-2026-64628 exists.

Affected product: getgrav grav. 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-2026-64628/ (Markdown: https://insights.sbomify.com/CVE-2026-64628/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-64628
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-64628
- OSV: https://osv.dev/vulnerability/CVE-2026-64628

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-64628/
Summaries are generated and may contain mistakes; the official description above is the record.