# CVE-2026-92592: Craft CMS before 4.18.6 Remote Code Execution via signed cookie

> Authenticated users can execute arbitrary OS commands via Twig injection in Craft CMS by exploiting a cookie signature reuse flaw.

- **Severity:** High 8.7 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA: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 Sep 2026
- **Updated:** 17 Sep 2026
- **Also known as:** GHSA-24f9-r76v-62p8, GHSA-5r92-75j8-c534

## What is CVE-2026-92592?

CVE-2026-92592 is a high-severity code injection vulnerability in craftcms cms, published on 16 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Craft CMS 4.8.0 through 4.18.5 and 5.0.0 through 5.10.12 sign an authenticated user's attacker-controlled license-shun cookie with the same key and format used to validate signed redirect parameters, because the HMAC signature is not bound to its purpose (Yii's cookieValidationKey is derived from the same Craft securityKey used for signed request parameters). An authenticated, non-administrator user (Control Panel access is not required) can set the cookie via the license-shun endpoint and transplant the signed envelope into the redirect parameter; on a successful login, Craft validates the signature and renders the authenticated bytes as an unsandboxed Twig template, where Twig's map filter accepts a string callback and allows PHP system() to execute arbitrary operating-system commands as the web-server user. Exploitation requires an account using password authentication without active 2FA, the default request configuration, and availability of PHP system(). The issue is fixed in 4.18.6 and 5.10.13.

Weakness: CWE-1336 (Improper Neutralization of Special Elements Used in a Template Engine)

## Which versions are affected by CVE-2026-92592?


## How do I fix CVE-2026-92592?

No fix has been published for CVE-2026-92592 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-92592 being exploited?

There is no known exploitation of CVE-2026-92592 in the wild and no public exploit code.

Public exploit code:

- Proof of concept for CVE-2026-92592: Craft CMS authenticated RCE (github_poc): https://github.com/godylockz/CVE-2026-92592

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-92592 and fix it if it is affected.

What it is: CVE-2026-92592 is a high-severity code injection vulnerability in craftcms cms, published on 16 Sep 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-2026-92592 in the wild and no public exploit code.

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-2026-92592/ (Markdown: https://insights.sbomify.com/CVE-2026-92592/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-92592
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-92592
- OSV: https://osv.dev/vulnerability/CVE-2026-92592

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-92592/
Summaries are generated and may contain mistakes; the official description above is the record.