CVE-2026-115457
HighCVSS 7.1Exploitation Probability (EPSS)
Low risk22th percentile - higher than 22% of all known CVEs
Summary
In baserCMS, 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.
Risk Assessment
An attacker can execute stored XSS in the browser of an administrator or other users, potentially leading to session hijacking, data theft, or actions performed on behalf of the victim. Other shortcodes, such as Mail.getForm, can also be abused to embed a working contact form with a valid CSRF token.
Recommendation
Update baserCMS to version 5.3.2 or 5.4.2, which patch the vulnerability. Consider disabling or restricting shortcode expansion in comments and monitor for unusual comments containing shortcodes.
Other vulnerabilities in baserCMS
See all- CVE-2026-97150High
When converting baserCMS4-style addons to baserCMS5-style ones, BcAddonMigrator includes 'config.php' from the addon, which means the PHP code in the file is executed. Arbitrary files on the system may be read or deleted by an administrative user.
- CVE-2017-10844High
baserCMS versions 3.0.14 and earlier, 4.0.5 and earlier allow an attacker to execute arbitrary PHP code on the server via unspecified vectors.
- CVE-2017-10843High
baserCMS versions 3.0.14 and earlier, 4.0.5 and earlier allow remote attackers to delete arbitrary files via unspecified vectors when the 'File' field is being used in the mail form.
- CVE-2016-4882High
CSRF vulnerability in baserCMS version 3.0.10 and earlier allows remote attackers to hijack the authentication of administrators via unspecified vectors.
- CVE-2016-4878High
The CSRF vulnerability in baserCMS version 3.0.10 and earlier allows remote attackers to hijack the authentication of administrators via unspecified vectors.
- CVE-2016-4876High
Version 3.0.10 and earlier of baserCMS contains a cross-site request forgery (CSRF) vulnerability that allows remote attackers to hijack the authentication of administrators and execute arbitrary PHP code via unspecified vectors.
- CVE-2017-10842Critical
A SQL injection vulnerability in baserCMS versions 3.0.14 and earlier, 4.0.5 and earlier allows remote attackers to execute arbitrary SQL commands via unspecified vectors.
- CVE-2026-115481High
In baserCMS, PermissionGroupsService::build() reads a plugin's config/permission.php to determine user group permissions. When that file is absent, it writes a wildcard allow rule for every non-admin group. BcCustomContent has no such file in any release, so after an administrator installs it, the default operators group can store and execute arbitrary PHP under the document root.
- CVE-2026-115480Medium
In baserCMS versions 5.0.0 before 5.3.2 and 5.4.0 before 5.4.2, the public mail message API endpoint does not enforce the form's auth_captcha setting. An unauthenticated attacker can automate submissions without solving the captcha.
- CVE-2026-115479Medium
In baserCMS versions 5.2.5 before 5.3.2 and 5.4.0 before 5.4.2, an unauthenticated visitor can supply a comma-separated address list in a public mail form's email field, causing a single auto-reply to be addressed to multiple third parties.
Original NVD description (English source)
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 data from NVD (NIST) · CISA KEV · EPSS