@angular/router: Denial of Service via RouterLink Query Parameter Retention in Server-Side Rendering (SSR)

{
  "id": "63ab25da7b068c62e2c1e4717f6294e8f6646ce71ee4d5a98a70da368b617751",
  "url": "https://osv.dev/vulnerability/GHSA-57xq-rjx2-v5xh",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "@angular/router: Denial of Service via RouterLink Query Parameter Retention in Server-Side Rendering (SSR)",
    "summary": "A denial of service (DoS) vulnerability was identified in `@angular/router` when Server-Side Rendering (SSR) is enabled on Node.js (V8) and `RouterLink` directives are rendered with `queryParamsHandling: 'merge'` or `'preserve'`, configured either per link or globally via `defaultQueryParamsHandling`. Starting in v21.2.0 ([angular/angular#66181](https://github.com/angular/angular/pull/66181)), `RouterLink` internals were refactored to use signals, introducing a computed signal (`_urlTree`) that cached the returned `UrlTree` instance on the directive. Because each rendered link maintains an active `RouterLink` instance for the entire duration of the request lifecycle, the computed signal permanently pinned the `UrlTree` and its associated query parameter dictionary in the heap until the SSR response completed. When query parameter handling is set to `'merge'` or `'preserve'`, each link copies the incoming request's query parameters into its own `UrlTree`. During SSR, memory consumption scales multiplicatively: $$\\text{Heap Retention} \\approx (\\text{Number of affected links}) \\times (\\text{Size of parsed query parameter map})$$ Because parsed JavaScript objects and property dictionaries require substantially more heap space than the raw query string—particularly when property names trigger dense array allocations under V8 property-storage heuristics—an attacker can supply oversized query strings to amplify heap consumption by orders of magnitude per in-flight request. ### Impac",
    "evidence": "osv:GHSA-57xq-rjx2-v5xh",
    "products": [
      {
        "name": {
          "value": "@angular/router",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "22.2.1",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": []
      },
      {
        "name": {
          "value": "@angular/router",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "21.2.25",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "GHSA-57xq-rjx2-v5xh",
      "aliases": [
        "CVE-2026-111751",
        "GHSA-57xq-rjx2-v5xh"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "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"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "22.0.0"
                },
                {
                  "fixed": "22.2.1"
                }
              ]
            }
          ],
          "package": {
            "name": "@angular/router",
            "purl": "pkg:npm/%40angular/router",
            "ecosystem": "npm"
          },
          "database_specific": {
            "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-57xq-rjx2-v5xh/GHSA-57xq-rjx2-v5xh.json"
          }
        },
        {
          "ranges": [
            {
              "type": "SEMVER",
              "events": [
                {
                  "introduced": "21.2.0"
                },
                {
                  "fixed": "21.2.25"
                }
              ]
            }
          ],
          "package": {
            "name": "@angular/router",
            "purl": "pkg:npm/%40angular/router",
            "ecosystem": "npm"
          },
          "database_specific": {
            "source": "https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/10/GHSA-57xq-rjx2-v5xh/GHSA-57xq-rjx2-v5xh.json"
          }
        }
      ],
      "modified": "2026-10-20T18:00:04.718890684Z",
      "provider": "osv",
      "references": [
        "https://github.com/angular/angular/security/advisories/GHSA-57xq-rjx2-v5xh",
        "https://github.com/angular/angular/issues/70908",
        "https://github.com/angular/angular/pull/70953",
        "https://github.com/angular/angular/commit/319a3c4f3268f4f96ac4acdbb118737d2261e0be",
        "https://github.com/angular/angular"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-400",
          "CWE-770"
        ],
        "severity": "HIGH",
        "github_reviewed": true,
        "nvd_published_at": null,
        "github_reviewed_at": "2026-10-20T17:52:32Z"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-111751",
        "evidence": "/aliases"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/database_specific/severity"
  },
  "source_id": "core-osv",
  "document_id": 390129,
  "published_at": "2026-10-20T17:52:32+00:00"
}