Angular: Security Vulnerabilities
The Angular SSR is a server-rise rendering tool for Angular applications. Versions on the 22.x branch prior to 22.0.0-next.2, the 21.x branch prior to 21.2.3, and the 20.x branch prior to 20.3.21 have an Open Redirect vulnerability in `@angular/ssr` due to an incomplete fix for CVE-2026-27738. While the original fix successfully blocked multiple leading slashes (e.g., `///`), the internal validation logic fails to account for a single backslash (`\`) bypass. When an Angular SSR application is deployed behind a proxy that passes the `X-Forwarded-Prefix` header, an attacker provides a value starting with a single backslash, the internal validation failed to flag the single backslash as invalid, the application prepends a leading forward slash, resulting in a `Location` header containing the URL, and modern browsers interpret the `/\` sequence as `//`, treating it as a protocol-relative URL and redirecting the user to the attacker-controlled domain. Furthermore, the response lacks the `Vary: X-Forwarded-Prefix` header, allowing the malicious redirect to be stored in intermediate caches (Web Cache Poisoning). Versions 22.0.0-next.2, 21.2.3, and 20.3.21 contain a patch. Until the patch is applied, developers should sanitize the `X-Forwarded-Prefix` header in their `server.ts` before the Angular engine processes the request.
CVSS Score
6.9
EPSS Score
0.0
Published
2026-03-26
Angular is a development platform for building mobile and desktop web applications using TypeScript/JavaScript and other languages. Prior to 22.0.0-next.3, 21.2.4, 20.3.18, and 19.2.20, a Cross-Site Scripting (XSS) vulnerability has been identified in the Angular runtime and compiler. It occurs when the application uses a security-sensitive attribute (for example href on an anchor tag) together with Angular's ability to internationalize attributes. Enabling internationalization for the sensitive attribute by adding i18n-<attribute> name bypasses Angular's built-in sanitization mechanism, which when combined with a data binding to untrusted user-generated data can allow an attacker to inject a malicious script. This vulnerability is fixed in 22.0.0-next.3, 21.2.4, 20.3.18, and 19.2.20.
CVSS Score
8.6
EPSS Score
0.0
Published
2026-03-16
Angular is a development platform for building mobile and desktop web applications using TypeScript/JavaScript and other languages. Versions prior to 21.2.0, 21.1.16, 20.3.17, and 19.2.19 have a cross-Site scripting vulnerability in the Angular internationalization (i18n) pipeline. In ICU messages (International Components for Unicode), HTML from translated content was not properly sanitized and could execute arbitrary JavaScript. Angular i18n typically involves three steps, extracting all messages from an application in the source language, sending the messages to be translated, and then merging their translations back into the final source code. Translations are frequently handled by contracts with specific partner companies, and involve sending the source messages to a separate contractor before receiving final translations for display to the end user. If the returned translations have malicious content, it could be rendered into the application and execute arbitrary JavaScript. When successfully exploited, this vulnerability allows for execution of attacker controlled JavaScript in the application origin. Depending on the nature of the application being exploited this could lead to credential exfiltration and/or page vandalism. Several preconditions apply to the attack. The attacker must compromise the translation file (xliff, xtb, etc.). Unlike most XSS vulnerabilities, this issue is not exploitable by arbitrary users. An attacker must first compromise an application's translation file before they can escalate privileges into the Angular application client. The victim application must use Angular i18n, use one or more ICU messages, render an ICU message, and not defend against XSS via a safe content security policy. Versions 21.2.0, 21.1.6, 20.3.17, and 19.2.19 patch the issue. Until the patch is applied, developers should consider reviewing and verifying translated content received from untrusted third parties before incorporating it in an Angular application, enabling strict CSP controls to block unauthorized JavaScript from executing on the page, and enabling Trusted Types to enforce proper HTML sanitization.
CVSS Score
7.6
EPSS Score
0.0
Published
2026-02-26
Angular is a development platform for building mobile and desktop web applications using TypeScript/JavaScript and other languages. Prior to versions 19.2.18, 20.3.16, 21.0.7, and 21.1.0-rc.0, a cross-site scripting (XSS) vulnerability has been identified in the Angular Template Compiler. The vulnerability exists because Angular’s internal sanitization schema fails to recognize the href and xlink:href attributes of SVG <script> elements as a Resource URL context. This issue has been patched in versions 19.2.18, 20.3.16, 21.0.7, and 21.1.0-rc.0.
CVSS Score
8.5
EPSS Score
0.0
Published
2026-01-10
Angular is a development platform for building mobile and desktop web applications using TypeScript/JavaScript and other languages. Prior to 21.0.2, 20.3.15, and 19.2.17, A Stored Cross-Site Scripting (XSS) vulnerability has been identified in the Angular Template Compiler. It occurs because the compiler's internal security schema is incomplete, allowing attackers to bypass Angular's built-in security sanitization. Specifically, the schema fails to classify certain URL-holding attributes (e.g., those that could contain javascript: URLs) as requiring strict URL security, enabling the injection of malicious scripts. This vulnerability is fixed in 21.0.2, 20.3.15, and 19.2.17.
CVSS Score
8.5
EPSS Score
0.0
Published
2025-12-01
A reflected cross-site scripting (XSS) vulnerability in CKeditor v46.1.0 & Angular v18.0.0 allows attackers to execute arbitrary code in the context of a user's browser via injecting a crafted payload.
CVSS Score
5.4
EPSS Score
0.0
Published
2025-11-07
A vulnerability was found in Angular up to 11.0.4/11.1.0-next.2. It has been classified as problematic. Affected is the handling of comments. The manipulation leads to cross site scripting. It is possible to launch the attack remotely but it might require an authentication first. Upgrading to version 11.0.5 and 11.1.0-next.3 is able to address this issue. The name of the patch is ba8da742e3b243e8f43d4c63aa842b44e14f2b09. It is recommended to upgrade the affected component.
CVSS Score
3.5
EPSS Score
0.012
Published
2022-05-26