CVE-2026-54267
MediumCVSS 6.1Exploitation Probability (EPSS)
Low risk8th percentile — higher than 8% of all known CVEs
Summary
Vulnerability in Angular prior to versions 22.0.1, 21.2.17, and 20.3.25 allows DOM Clobbering attack on SSR hydration mechanism. An attacker can replace the DOM element with id 'ng-state' before the state script is loaded, leading to parsing controlled data as JSON.
Risk Assessment
The risk involves injecting malicious data into the hydration process, potentially causing incorrect application behavior or client state takeover.
Recommendation
Immediately update Angular to version 22.0.1, 21.2.17, or 20.3.25 depending on the branch used. Additionally, avoid binding untrusted data to the 'id' attribute of DOM elements.
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 22.0.1, 21.2.17, and 20.3.25, to optimize client-side bootstrap in Server-Side Rendered (SSR) environments, Angular supports Hydration via provideClientHydration(). During SSR, Angular serializes the application's runtime state (such as cached HttpClient responses) and outputs it into the HTML stream as a <script> tag with a predictable identifier. During client bootstrap, Angular recovers this state by looking up the element via document.getElementById('ng-state') and parsing its text content. Because the DOM element lookup for the state container is predictable and relies solely on the ID selector (ng-state), it is susceptible to DOM Clobbering. If the application binds untrusted user input or CMS content to element properties such as id (e.g., <div [id]="userInput"> or <a id="ng-state">) before the genuine <script> tag is parsed by the browser, the attacker-controlled element takes precedence in the DOM lookup. During hydration, when Angular calls document.getElementById('ng-state'), the browser returns the attacker's clobbered element. Angular then attempts to parse the text content or attributes of this clobbered element as JSON. This vulnerability is fixed in 22.0.1, 21.2.17, and 20.3.25.