Vulnerability · Published Nov 23, 2020 · Assigned by GitHub_M
CVE-2020-15249Stored XSS by authenticated backend user with access to upload files
Low 2.8
In plain English
A low-severity cross-site scripting in october from octobercms. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 40% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
October is a free, open-source, self-hosted CMS platform based on the Laravel PHP Framework. In October CMS from version 1.0.319 and before version 1.0.469, backend users with access to upload files were permitted to upload SVG files without any sanitization applied to the uploaded files. Since SVG files support being parsed as HTML by browsers, this means that they could theoretically upload Javascript that would be executed on a path under the website's domain (i.e. /storage/app/media/evil.svg), but they would have to convince their target to visit that location directly in the target's browser as the backend does not display SVGs inline anywhere, SVGs are only displayed as image resources in the backend and are thus unable to be executed. Issue has been patched in Build 469 (v1.0.469) & v1.1.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Packagist | october/backend | 1.0.469 | GHSA-fx3v-553x-3c4q |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| octobercms | october | >= 1.0.319, < 1.0.469 |
Weakness: CWE-79 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N