XSS in Baserproject Basercms
CVE-2026-115457
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.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- Baserproject Basercms — versions >= 5.0.0, < 5.3.2, >= 5.4.0, < 5.4.2
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-115457?
- CVE-2026-115457 is a high-severity vulnerability in Baserproject Basercms, classified under Cross-site Scripting. CVSS score: 7.1/10. Published 2026-10-23.
- How severe is CVE-2026-115457?
- High severity. CVSS v3 base score is 7.1 out of 10.