CVE-2026-88059
MediumCVSS 4.0Exploitation Probability (EPSS)
Low risk22th percentile - higher than 22% of all known CVEs
Summary
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.
Risk Assessment
Authenticated user data may leak to other users through shared cached HTML, leading to a confidentiality breach. The risk occurs when SSR responses are shared by a CDN, reverse proxy, or application cache.
Recommendation
Upgrade Angular to version 20.3.28, 21.2.20, or 22.1.1. As a workaround, attach credentials at the child level, filter sensitive endpoints with withHttpTransferCacheOptions, or mark personalized HTML as private/no-store.
Other vulnerabilities in Angular
See all- CVE-2026-88060High
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-2026-88058High
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-2026-88056High
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-2026-69151Medium
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-2026-50555Medium
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.
- 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 20.3.28, 21.2.20, and 22.1.1, Angular's @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. Exploitation requires provideClientHydration, child provideHttpClient delegation through withRequestsMadeViaParent, parent-level credential injection, and an SSR HTML response shared across users by a CDN, reverse proxy, or application cache. A later unauthenticated or unauthorized visitor can receive the cached HTML containing the earlier authenticated user's sensitive response data. Applications can mitigate by attaching credentials at the child, filtering sensitive endpoints with withHttpTransferCacheOptions, disabling transfer caching for sensitive routes, or marking personalized HTML private or no-store. This issue is fixed in versions 20.3.28, 21.2.20, and 22.1.1.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS