October CMS has Stored XSS in its Backend Editor Markup Classes
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- Passive
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Cross-site scripting
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-79.
Summary
October is a Content Management System (CMS) and web platform. Versions prior to 3.7.14 and 4.1.10 contain a Stored Cross-Site Scripting (XSS) vulnerability in the Backend Editor Settings. The Markup Classes fields (used for paragraph styles, inline styles, table styles, etc.) did not sanitize input to valid CSS class name characters. Malicious values were rendered unsanitized in Froala editor dropdown menus, allowing JavaScript execution when any user opened a RichEditor. Exploitation could lead to privilege escalation if a superuser opens any RichEditor during routine content editing (e.g., editing a blog post), and requires authenticated backend access with editor settings permissions. This issue has been fixed in versions 3.7.14 and 4.1.10. To workaround this issue, restrict editor settings permissions to fully trusted administrators only
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| October CMS | october | before 3.7.14; 4.0.0 to before 4.1.10 | 3.7.14, 4.1.10 | Patch available | CNA |
| — | october/system (Packagist) | 4.0.0 to before 4.1.10 | 4.1.10 | Patch available | GHSA-6qmh-j78v-ffp7 |
| — | october/system (Packagist) | before 3.7.14 | 3.7.14 | Patch available | GHSA-6qmh-j78v-ffp7 |
- october VendorOctober CMS Affected before 3.7.14; 4.0.0 to before 4.1.10 Fixed in 3.7.14, 4.1.10 Patch available CNA
- october/system (Packagist) Vendor— Affected 4.0.0 to before 4.1.10 Fixed in 4.1.10 Patch available GHSA-6qmh-j78v-ffp7
- october/system (Packagist) Vendor— Affected before 3.7.14 Fixed in 3.7.14 Patch available GHSA-6qmh-j78v-ffp7
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:octobercms:october:*:*:*:*:*:*:*:* | up to 3.7.13; 4.0.0 – 4.1.9 | Vulnerable | October CMS |
- cpe:2.3:a:octobercms:october:*:*:*:*:*:*:*:* Versions up to 3.7.13; 4.0.0 – 4.1.9 Vulnerable ·October CMS
Remediation
- Fix · CNA october (octobercms) Fixed in 3.7.14, 4.1.10
- Fix · GHSA-6qmh-j78v-ffp7 october/system (Packagist) Fixed in 4.1.10 Advisory →
- Fix · GHSA-6qmh-j78v-ffp7 october/system (Packagist) Fixed in 3.7.14 Advisory →
Timeline
- 2026-10-02 Threatist record created from CVE-2026-24906
- 2026-10-03 Alias added: GHSA-6qmh-j78v-ffp7
References
More October CMS October vulnerabilities
- TI-2021-12316 Account Takeover in Octobercms KEVCVSS 3.1CRITICAL 9.1
- TI-2021-12318 Arbitrary code execution in october/system CVSS 3.1HIGH 8.8
- TI-2017-14456 October CMS build 412 is vulnerable to PHP code execution in the file upload… CVSS 3.0HIGH 7.2
- TI-2023-23545 A Cross-Site Scripting (XSS) vulnerability in installation of October v.3.4.16 allows an… CVSS 3.1MEDIUM 5.4
- TI-2023-19223 An arbitrary file upload vulnerability in October CMS v3.4.4 allows attackers to execute… CVSS 3.1MEDIUM 5.4
- TI-2024-30847 October 3.6.30 allows an authenticated admin account to upload a PDF file containing… CVSS 3.1MEDIUM 4.7
Sources
- CVE-2026-24906 · CVE Program
- CVE-2026-24906 · NVD
- FIRST EPSS
- GHSA-6qmh-j78v-ffp7 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences