Cyber Posture

CVE-2025-26555

High

Published: 15 March 2025

Published
15 March 2025
Modified
23 April 2026
KEV Added
Patch
CVSS Score 7.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L
EPSS Score 0.0009 25.0th percentile
Risk Priority 14 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-26555 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 Exploit Public-Facing Application (T1190); ranked at the 25.0th 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-15 (Information Output Filtering) and SI-2 (Flaw Remediation).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190). What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

SI-15 requires output filtering to neutralize untrusted input before web page generation, directly preventing reflected XSS in the Debug-Bar-Extender plugin.

prevent

SI-10 enforces input validation at system entry points, mitigating malicious payloads targeting the improper neutralization vulnerability in CVE-2025-26555.

prevent

SI-2 mandates timely identification, reporting, and correction of flaws like the reflected XSS in Debug-Bar-Extender through patching and remediation processes.

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Why these techniques?

The reflected XSS vulnerability in the public-facing WordPress plugin directly enables remote exploitation of a web application weakness to execute arbitrary scripts in the victim's browser.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

NVD Description

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Thorsten Ott Debug-Bar-Extender debug-bar-extender allows Reflected XSS.This issue affects Debug-Bar-Extender: from n/a through <= 0.5.

Deeper analysisAI

CVE-2025-26555 is an Improper Neutralization of Input During Web Page Generation vulnerability, classified as Reflected Cross-site Scripting (XSS) under CWE-79, in the Debug-Bar-Extender WordPress plugin developed by Thorsten Ott. The issue affects all versions of Debug-Bar-Extender from n/a through 0.5 inclusive, allowing malicious input to be reflected in web page generation without proper neutralization.

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 network accessibility, low attack complexity, no required privileges, and user interaction such as clicking a malicious link. Remote attackers can exploit it to execute arbitrary scripts in the context of a victim's browser, achieving low impacts on confidentiality, integrity, and availability with a changed scope.

Mitigation details are available in the Patchstack advisory at https://patchstack.com/database/Wordpress/Plugin/debug-bar-extender/vulnerability/wordpress-debug-bar-extender-plugin-0-5-reflected-cross-site-scripting-xss-vulnerability?_s_id=cve, which covers the WordPress Debug-Bar-Extender plugin 0.5 reflected XSS vulnerability.

Details

CWE(s)

CVEs Like This One

CVE-2026-23807Shared CWE-79
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CVE-2026-0800Shared CWE-79
CVE-2025-46199Shared CWE-79
CVE-2024-56060Shared CWE-79
CVE-2025-23570Shared CWE-79
CVE-2024-56056Shared CWE-79
CVE-2025-70038Shared CWE-79
CVE-2025-64054Shared CWE-79

References