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-2026-88056Critical
Angular before 20.3.30, 21.2.22, and 22.1.4 has a server-side rendering (SSR) vulnerability in @angular/platform-server. The resolveUrl and parseUrl utilities call String.prototype.trim(), which removes leading Unicode whitespace after a same-origin check, converting a relative path into an attacker-controlled protocol-relative URL, leading to SSRF and credential disclosure.
- CVE-2026-88060Medium
Angular before 20.3.30, 21.2.22, and 22.1.4 has a server-side rendering (SSR) vulnerability in @angular/platform-server. Serialization of untrusted input inside fallback raw-content elements (noscript, iframe, noembed, noframes) fails to escape matching closing tags, enabling arbitrary JavaScript execution.
- CVE-2026-88059Medium
In Angular prior to 20.3.28, 21.2.20, and 22.1.1, @angular/common HttpTransferCache can cache an authenticated response when Server-Side Rendering (SSR) and hydration use a hierarchical HttpClient configured with withRequestsMadeViaParent. The child TransferCache evaluates an initially anonymous request before delegation, then a parent withInterceptors chain adds an Authorization header, cookie, or API token; although the parent cache skips the authenticated request, the child still stores the private response in TransferState serialized as JSON in the ng-state script. A later unauthenticated or unauthorized visitor can receive the cached HTML containing the earlier authenticated user's sensitive response data.
- CVE-2026-88058Medium
Angular before 20.3.30, 21.2.22, and 22.1.4 has a server-side rendering (SSR) vulnerability in @angular/platform-server. Serialization of ProcessingInstruction DOM nodes inside fallback raw-content elements fails to escape matching ancestor closing tags, allowing premature container termination and arbitrary JavaScript execution.
- CVE-2026-88057Medium
In Angular prior to 20.3.28, 21.2.20, and 22.1.0, the compiler and runtime in @angular/core and @angular/compiler could omit or select an incorrect sanitizer for security-sensitive directive host bindings because SecurityContext was derived from the declaring directive or component selector rather than the concrete host element. The mismatch is reachable through hostDirectives composition, inherited HostBinding declarations, createComponent with a custom hostElement or dynamic directives, SVG/MathML namespace elements, and tag-neutral selectors such as :not(...). Attacker-controlled href, src, action, xlink:href, or data values can therefore reach DOM attributes without Angular's built-in sanitizer and execute arbitrary JavaScript in the user's browser context.
- 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.
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

