{
  "affected": [
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "symfony/routing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5.4.53"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "symfony/routing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.0.0"
            },
            {
              "fixed": "6.4.41"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "symfony/routing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "7.0.0"
            },
            {
              "fixed": "7.4.13"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "symfony/routing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "8.0.0"
            },
            {
              "fixed": "8.0.13"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "symfony/symfony"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5.4.53"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "symfony/symfony"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.0.0"
            },
            {
              "fixed": "6.4.41"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "symfony/symfony"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "7.0.0"
            },
            {
              "fixed": "7.4.13"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "symfony/symfony"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "8.0.0"
            },
            {
              "fixed": "8.0.13"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-48784"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-172",
      "CWE-601"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-15T17:33:46Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "### Description\n\n`Symfony\\Component\\Routing\\Generator\\UrlGenerator::doGenerate()` percent-encodes `.` and `..` path segments so that the generated URL still resolves to the originating route after RFC 3986 \u00a75.2.4 dot-segment removal (which strict RFC-3986 consumers \u2014 routers, reverse proxies, HTTP clients \u2014 perform *before* percent-decoding).\n\nThe encoding was implemented as `strtr($url, [\u0027/../\u0027 =\u003e \u0027/%2E%2E/\u0027, \u0027/./\u0027 =\u003e \u0027/%2E/\u0027])` plus a trailing-segment fixup. `strtr` advances past the trailing `/` of each match, so the next dot-segment in a chained sequence was left unescaped:\n\n| Input                | Output (before fix)                      | Expected                            |\n| -------------------- | ---------------------------------------- | ----------------------------------- |\n| `/../../../`         | `/%2E%2E/../%2E%2E/`                     | `/%2E%2E/%2E%2E/%2E%2E/`            |\n| `/foo/../../../bar`  | `/foo/%2E%2E/../%2E%2E/bar`              | `/foo/%2E%2E/%2E%2E/%2E%2E/bar`     |\n\nWhen a route exposes a parameter constrained by a permissive requirement (`.+`, `.*`, or similar) that accepts dots and slashes, attacker-controlled chained `..` or `.` segments produce a generated URL that, under strict RFC 3986 normalization, collapses to a different path than the originating route. The Twig `path()` / `url()` helpers and any server-side use of `UrlGenerator` are affected. Same class of route round-trip integrity issue as CVE-2026-45065.\n\nNote: WHATWG-conformant browsers treat `%2E`/`%2E%2E` as dot-segments during URL parsing, so the encoding never protected browser-side traversal. The defense exists for RFC-3986-conformant consumers; restoring it for chained segments closes the gap there.\n\n### Resolution\n\n`UrlGenerator` now matches every `/.` or `/..` dot-segment in a single left-to-right `preg_replace_callback` pass using a lookahead that does not consume the trailing `/`, so adjacent dot-segments are encoded correctly.\n\nThe patches for this issue are available [here](https://github.com/symfony/symfony/commit/4b63c3a3f7af04ecd79c89a594b0b02a01990b1d) for branch 5.4 (and forward-ported to 6.4, 7.4, 8.0 and 8.1).\n\n### Credits\n\nSymfony would like to thank Alex Pott for reporting the issue and Nicolas Grekas for providing the fix.",
  "id": "GHSA-h5x3-xfc9-m39h",
  "modified": "2026-06-15T17:33:46Z",
  "published": "2026-06-15T17:33:46Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/symfony/symfony/security/advisories/GHSA-h5x3-xfc9-m39h"
    },
    {
      "type": "WEB",
      "url": "https://github.com/symfony/symfony/commit/4b63c3a3f7af04ecd79c89a594b0b02a01990b1d"
    },
    {
      "type": "WEB",
      "url": "https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/routing/CVE-2026-48784.yaml"
    },
    {
      "type": "WEB",
      "url": "https://github.com/FriendsOfPHP/security-advisories/blob/master/symfony/symfony/CVE-2026-48784.yaml"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/symfony/symfony"
    },
    {
      "type": "WEB",
      "url": "https://symfony.com/cve-2026-48784"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Symfony: UrlGenerator Dot-Segment Encoding Skips Every Other Chained `../` or `./` \u2192 Generated URL Collapses Off-Route Under RFC 3986 Normalization"
}