CVE record
CVE-2026-28697
Craft Affected by Authenticated RCE via "craft.app.fs.write()" in Twig Templates
Craft is a content management system (CMS). Prior to 4.17.0-beta.1 and 5.9.0-beta.1, an authenticated administrator can achieve Remote Code Execution (RCE) by injecting a Server-Side Template Injection (SSTI) payload into Twig template fields (e.g., Email Templates). By calling the craft.app.fs.write() method, an attacker can write a malicious PHP script to a web-accessible directory and subsequently access it via the browser to execute arbitrary system commands. This vulnerability is fixed in 4.17.0-beta.1 and 5.9.0-beta.1.
CVE evidence
Known exploitation
Not listed in fetched KEV catalog
Absence from the fetched catalog does not establish that exploitation has not occurred.
Severity
critical
CVSS 9.4 · CVSS_V4
Affected packages
1
Supported package records returned by OSV. Vendor and product names are not used to infer matches.
OSV package mapping
Affected open-source packages
| Package | Ecosystem | Fixed versions |
|---|---|---|
| craftcms/cms | composer | 5.9.0-beta.1, 4.17.0-beta.1 |