CVE-2026-25369
Published: 16 March 2026
Summary
CVE-2026-25369 is a high-severity Cross-site Scripting (CWE-79) vulnerability. Its CVSS base score is 7.1 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Drive-by Compromise (T1189); ranked at the 11.8th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-15 (Information Output Filtering).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
Directly mitigates reflected XSS by filtering malicious scripts from user inputs reflected in web page outputs generated by the Flexmls IDX plugin.
Validates and sanitizes user inputs to prevent malicious JavaScript payloads from being accepted and processed by the vulnerable flexmls-idx plugin.
Remediates the specific improper neutralization flaw in flexmls-idx versions through <=3.15.9 by identifying, patching, and deploying updates.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Reflected XSS directly enables arbitrary JS execution in the victim's browser via crafted links to the vulnerable plugin, facilitating drive-by compromise (T1189), browser session hijacking (T1185), and stealing web session cookies (T1539) for data theft or hijacking.
NVD Description
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in flexmls Flexmls® IDX flexmls-idx allows Reflected XSS.This issue affects Flexmls® IDX: from n/a through <= 3.15.9.
Deeper analysisAI
CVE-2026-25369 is an Improper Neutralization of Input During Web Page Generation vulnerability, classified as Reflected Cross-site Scripting (XSS) under CWE-79, affecting the Flexmls® IDX WordPress plugin (flexmls-idx). This issue impacts all versions from n/a through 3.15.9, where user input is not properly sanitized during web page generation, allowing malicious scripts to be reflected back to users.
The vulnerability carries a CVSS v3.1 base score of 7.1 (AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L), indicating it is exploitable over the network with low attack complexity, no privileges required, but necessitating user interaction such as clicking a malicious link. Any unauthenticated attacker can craft and distribute payloads that, when processed by the plugin, execute arbitrary JavaScript in the victim's browser context, potentially enabling session hijacking, data theft, or other client-side attacks with low impacts on confidentiality, integrity, and availability across a changed scope.
The Patchstack advisory (https://patchstack.com/database/Wordpress/Plugin/flexmls-idx/vulnerability/wordpress-flexmls-idx-plugin-3-15-9-reflected-cross-site-scripting-xss-vulnerability?_s_id=cve) documents this Reflected XSS in the flexmls-idx WordPress plugin up to version 3.15.9, recommending mitigation through updating to a patched version of the plugin where available.
Details
- CWE(s)