CVE-2026-50555
MediumCVSS 6.1Exploitation Probability (EPSS)
Low risk6th percentile - higher than 6% of all known CVEs
Summary
A Cross-Site Scripting (XSS) vulnerability exists in Angular's @angular/platform-server DOM emulation dependency (domino) when serializing raw-text elements like <script>, <style>, and <iframe>. A Unicode index alignment bug causes dynamic text with astral characters (e.g., emojis) before a closing tag to be improperly escaped, allowing JavaScript injection. The flaw is fixed in versions 22.0.0-rc.2, 21.2.16, 20.3.24, and 19.2.25.
Risk Assessment
An attacker can exploit this vulnerability to execute arbitrary JavaScript in the victim's origin context during server-side rendering (SSR), leading to data theft, session hijacking, or page content manipulation.
Recommendation
Immediately upgrade Angular to one of the patched versions: 22.0.0-rc.2, 21.2.16, 20.3.24, or 19.2.25. If upgrading is not possible, avoid using @angular/platform-server with dynamic content containing astral characters in raw-text elements.
Other vulnerabilities in Angular
See all- CVE-2026-69151Medium
Angular prior to versions 20.3.27, 21.2.19, and 22.0.1 contains a vulnerability in the Angular compiler i18n pipeline that permits i18n-onerror and other i18n-on event-handler attributes. This allows a lower-trust translation file to replace a static handler with executable JavaScript.
- CVE-2026-69149Medium
Angular prior to versions 20.3.27, 21.2.19, and 22.0.7 contains a Cross-Site Scripting (XSS) vulnerability in @angular/platform-server's DOM emulation dependency (domino) when serializing the content of fallback raw-content elements (<iframe>, <noembed>, <noframes>, and <noscript>).
- CVE-2026-68945Medium
Angular prior to versions 20.3.27, 21.2.19, and 22.0.2 contains a vulnerability in HttpTransferCache that comma-joins repeated request parameters. This allows semantically distinct HttpClient requests to use the same transfer-cache key and reuse a wrong backend response.
- CVE-2026-50556Medium
A Cross-Site Scripting (XSS) vulnerability exists in Angular's @angular/platform-server component when serializing <noscript> elements during SSR. The domino library fails to escape </noscript> in dynamic content, allowing injection of malicious scripts.
- CVE-2026-54267Medium
A DOM Clobbering vulnerability in Angular allows an attacker to replace the SSR state container (ng-state) by injecting an HTML element with the same ID. During client hydration, Angular reads data from the fake element, potentially leading to code execution or data theft.
- CVE-2026-54266Medium
A vulnerability in Angular prior to versions 22.0.1, 21.2.17, and 20.3.25 allows an attacker to overwrite HTTP responses in the TransferState cache during Server-Side Rendering (SSR). The weak 32-bit DJB2 hash used for cache key generation enables hash collisions, causing sensitive endpoint responses to be replaced with responses from other requests.
- CVE-2026-50557Medium
A vulnerability in Angular's @angular/compiler and @angular/core packages allows bypassing element and attribute sanitization via namespace workarounds. An attacker can inject a malicious template with custom namespaces, leading to client-side Cross-Site Scripting (XSS).
- CVE-2026-27970Medium
An XSS vulnerability in the Angular i18n pipeline allows arbitrary JavaScript execution if an attacker compromises the translation file. Affects versions prior to 21.2.0, 21.1.16, 20.3.17, and 19.2.19 due to unsanitized HTML in ICU messages.
- CVE-2024-21490High
This vulnerability affects angular package versions from 1.3.0 and angularjs package versions from 1.3.0. A regular expression used to split the value of the ng-srcset directive is vulnerable to catastrophic backtracking, leading to super-linear runtime. With large crafted input, this can cause a denial of service (DoS). The package is End-of-Life (EOL) and will not receive fixes.
Original NVD description (English source)
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, 21.2.16, 20.3.24, and 19.2.25, a Cross-Site Scripting (XSS) vulnerability exists in @angular/platform-server's DOM emulation dependency (domino) when serializing the content of raw-text elements (such as <script>, <style>, and <iframe>). domino supports escaping raw-text elements during serialization to prevent closing-tag breakout. However, a Unicode index alignment bug existed in this escaping logic. In JavaScript, string lengths and character indices are calculated based on UTF-16 code units (where astral characters—such as emojis—occupy 2 code units / 4 bytes). If the bound dynamic text contained astral Unicode characters before the closing tag (e.g. </script>, </style>, or </iframe>), the index offset calculation in domino's replacement logic shifted. This misalignment caused domino to fail to replace or escape the closing tag, leaving it raw and unescaped in the output HTML. An attacker who controls the dynamic text can supply a payload containing both an astral Unicode character and a closing tag (e.g., 😀</iframe><script>alert(1)</script>). When serialized on the server during SSR, the browser parses the unescaped closing tag, exits the raw-text context early, and executes the subsequent <script> block, leading to same-origin Cross-Site Scripting (XSS). This vulnerability is fixed in 22.0.0-rc.2, 21.2.16, 20.3.24, and 19.2.25.