CVE-2026-115457: high-severity vulnerability in baserproject basercms
baserCMS: Unauthenticated Stored XSS via Shortcode Expansion in Blog Comments
Published · Updated
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21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.1epss 0.4%
baserCMS is a website development framework. In versions 5.0.0 before 5.3.2 and 5.4.0 before 5.4.2, global shortcode expansion runs over the complete rendered page, including HTML-escaped blog comments supplied by unauthenticated visitors. A comment containing the BcBaser.getGoogleMaps shortcode can set apiBaseUrl to an attacker-controlled script URL, which is emitted as a script src and executes JavaScript on the site's origin when another visitor or administrator opens the article displaying that comment. Escaping raw HTML in comments does not prevent this stored cross-site scripting because shortcode processing happens after HTML rendering. Other registered shortcodes also expand in comments; Mail.getForm can embed a working contact form with a valid CSRF token. The flaw can compromise the authenticated browser context of an administrator who views the affected article. This issue has been patched in versions 5.3.2 and 5.4.2.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N
Affected products
baserproject · basercmsRelated CVEs — baserproject basercms
In the same product, most dangerous first.
CVE-2026-21861CRITICALbaserCMS: OS Command Injection Leading to Remote Code Execution (RCE)EPSS 2.3%CVE-2020-15277HIGHRemote Code Execution in baserCMSEPSS 2.3%CVE-2021-41243CRITICALOS Command Injection Vulnerability and Potential Zip Slip VulnerabilityEPSS 2.2%CVE-2020-15159HIGHCross Site Scripting leading to RCE in baserCMSEPSS 2.2%CVE-2026-30880CRITICALbaserCMS: OS command injection vulnerability in installerEPSS 2.1%CVE-2021-41279HIGHZip Slip Vulnerability in BaserCMSEPSS 1.6%