CVE-2026-28697
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).
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.07%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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.
- CVSS 4.0
- 9.4 CRITICALCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 1.07% probability · 63th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-1336
- Affected
- craftcms/craft cms
- Source
- security-advisories@github.com
References
- https://github.com/craftcms/cms/commit/9dc2a4a3ec8e9cd5e8c0d1129f36371437519197Patch
- https://github.com/craftcms/cms/pull/18216Issue Tracking, Patch
- https://github.com/craftcms/cms/pull/18219Issue Tracking, Patch
- https://github.com/craftcms/cms/security/advisories/GHSA-v47q-jxvr-p68xExploit, Mitigation, Patch, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.