Angular: Template and Attribute Namespace Sanitization Bypass (XSS)_CVE-2026-50557

5.3 / 10

MEDIUM

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

Description

Angular is a development platform for building mobile and desktop web applications using TypeScript/JavaScript and other languages. Prior to 22.0.0-rc.2, 21.2.15, 20.3.22 and 19.2.22, an issue in the @angular/compiler and @angular/core packages allows bypassing element and attribute sanitization/validation through specific namespace workarounds. Specifically, namespaced script elements (e.g., <svg:script> or <:svg:script>) were not properly identified as script elements by the Angular template preparser, allowing them to pass through template compilation without being stripped. Furthermore, security context schema mappings for element attributes did not consistently handle attributes within namespaced elements (like SVG and MathML), opening up gaps where malicious namespaced attributes could bypass runtime and compile-time sanitizers. Combined, these flaws enable an attacker who can inject or supply a template/tag structure with custom namespaces to bypass Angular's script-stripping logic and attribute sanitizers, leading to client-side Cross-Site Scripting (XSS). This vulnerability is fixed in 22.0.0-rc.2, 21.2.15, 20.3.22 and 19.2.22.

Basic Information

ID CVE-2026-50557

Source GitHub_M

Published Jun 22, 2026 at 15:11

Affected Product

Vendor angular

Product angular

Version >= 21.0.0-next.0 < 21.2.15

Affected Versions angular angular >= 21.0.0-next.0 < 21.2.15
angular angular >= 22.0.0-next.0 < 22.0.0-rc.2
angular angular >= 20.0.0-next.0 < 20.3.22
angular angular >= 19.0.0-next.0 < 19.2.22
angular angular <= 18.2.14

CWE Classification

CWE-79

References

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