7.1
HIGH CVSS 3.1
CVE-2026-115457
baserCMS: Unauthenticated Stored XSS via Shortcode Expansion in Blog Comments
Description

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.

INFO

Published Date :

Oct. 23, 2026, 2:17 p.m.

Last Modified :

Oct. 23, 2026, 4:28 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-115457 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Basercms basercms
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH [email protected]
Solution
Update baserCMS to patched versions to fix stored XSS via shortcode expansion in comments.
  • Update baserCMS to version 5.3.2 or later.
  • Update baserCMS to version 5.4.2 or later.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-115457 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-115457 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-115457 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-115457 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Oct. 23, 2026

    Action Type Old Value New Value
    Added Description 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.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:N
    Added CWE CWE-79
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/115xxx/CVE-2026-115457.json">CVE-2026-115457</a>
    Added Reference https://github.com/baserproject/basercms/commit/bec4776ab497457fac76da7ae67d2dd0ad964eec
    Added Reference https://github.com/baserproject/basercms/releases/tag/5.3.2
    Added Reference https://github.com/baserproject/basercms/releases/tag/5.4.2
    Added Reference https://github.com/baserproject/basercms/security/advisories/GHSA-qhv2-3j2q-v43x
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.