Cyber Posture

CVE-2026-42733

High

Published: 27 May 2026

Published
27 May 2026
Modified
27 May 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 0.0003 10.2th percentile
Risk Priority 14 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-42733 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 Browser Session Hijacking (T1185); ranked at the 10.2th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

Threat & Defense at a Glance

What attackers do: exploitation maps to Browser Session Hijacking (T1185) and 2 other techniques.
Threat & Defense Details

Likely Mitigating ControlsAI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

addresses: CWE-79

Validates web inputs to reject script-related content that could produce XSS.

addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

MITRE ATT&CK Enterprise TechniquesAI

T1185 Browser Session Hijacking Collection
Adversaries may take advantage of security vulnerabilities and inherent functionality in browser software to change content, modify user-behaviors, and intercept information as part of various browser session hijacking techniques.
T1539 Steal Web Session Cookie Credential Access
An adversary may steal web application or service session cookies and use them to gain access to web applications or Internet services as an authenticated user without needing credentials.
T1056.003 Web Portal Capture Collection
Adversaries may install code on externally facing portals, such as a VPN login page, to capture and transmit credentials of users who attempt to log into the service.
Why these techniques?

DOM-based XSS directly enables browser session hijacking, web session cookie theft, and web portal input capture via injected client-side scripts.

Confidence: MEDIUM · MITRE ATT&CK Enterprise v18.1

NVD Description

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in RealMag777 WPCS currency-switcher allows DOM-Based XSS.This issue affects WPCS: from n/a through <= 1.3.1.

Deeper analysisAI

Automated synthesis unavailable for this CVE.

Details

CWE(s)
OWASP Top 10 Web 2025

EU & UK References

References