Angular is a development platform for building mobile and desktop web applications using TypeScript/JavaScript and other languages. Prior to 20.3.32, 21.2.24, and 22.2.0, the @angular/router URL parser stores numeric matrix parameter names and numeric outlet names as properties on initially empty JavaScript objects during Node.js server-side rendering. V8 can interpret these URL-derived keys as array indices and allocate dense backing stores sized to high numeric values, so repeated small path segments cause disproportionate per-segment heap consumption. An unauthenticated attacker can send overlapping requests containing repeated numeric matrix parameters when SSR is enabled, the router directly parses the request URL, and upstream proxies allow semicolons and multiple path segments, eventually exhausting the Node.js old-space heap and terminating the SSR worker. Pure client-side Angular applications are not affected. This issue is fixed in versions 20.3.32, 21.2.24, and 22.2.0.
https://github.com/angular/angular/security/advisories/GHSA-ff3f-86qr-9cv3
https://github.com/angular/angular/releases/tag/v22.2.0
https://github.com/angular/angular/releases/tag/v21.2.24
https://github.com/angular/angular/releases/tag/v20.3.32
https://github.com/angular/angular/pull/70717
https://github.com/angular/angular/issues/70716
https://github.com/angular/angular/commit/ddfe21072ba32ca4cd9d7d3c6b7df66af81d58c4
https://github.com/angular/angular/commit/5af61216eab8bf4a6697a1d79bda3d857c06f89d
https://github.com/angular/angular/commit/03872a80bcf1c89b2b04cdd3f444b2ee954da583
Published: 2026-10-14
Updated: 2026-10-20
Base Score: 5
Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P
Severity: Medium
Base Score: 7.5
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Severity: High
Base Score: 8.2
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Severity: High
EPSS: 0.00756