Vulnerability-Lookup

GHSA-RXV8-25V2-QMQ8

Vulnerability from github – Published: 2026-06-04 15:23 – Updated: 2026-06-04 15:23

Summary

React Router vulnerable to Denial of Service via reflected user input in single-fetch

Details

A DoS vulnerability exists in the React Router v7 Framework Mode, as well as Remix v2.9.0+ with Single Fetch enabled. In some scenarios the underlying serialization algorithm can become a bottleneck when encoding specific types of data into server responses. Please upgrade to React Router v7.14.0 or later.

[!NOTE] This does not impact your React Router application if you are using Declarative Mode (<BrowserRouter>) or Data Mode (createBrowserRouter/<RouterProvider>).

Severity

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "react-router"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "7.0.0"
            },
            {
              "fixed": "7.14.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "turbo-stream"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.0.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-34077"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-04T15:23:51Z",
    "nvd_published_at": "2026-06-02T20:16:34Z",
    "severity": "HIGH"
  },
  "details": "A DoS vulnerability exists in the React Router v7 [Framework Mode](https://reactrouter.com/start/modes#framework), as well as Remix v2.9.0+ with [Single Fetch](https://v2.remix.run/docs/guides/single-fetch) enabled. In some scenarios the underlying serialization algorithm can become a bottleneck when encoding specific types of data into server responses.  Please upgrade to React Router v7.14.0 or later.\n\n\u003e [!NOTE]\n\u003e This does not impact your React Router application if you are using [Declarative Mode](https://reactrouter.com/start/modes#declarative) (`\u003cBrowserRouter\u003e`) or [Data Mode](https://reactrouter.com/start/modes#data) (`createBrowserRouter`/`\u003cRouterProvider\u003e`).",
  "id": "GHSA-rxv8-25v2-qmq8",
  "modified": "2026-06-04T15:23:51Z",
  "published": "2026-06-04T15:23:51Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/remix-run/react-router/security/advisories/GHSA-rxv8-25v2-qmq8"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-34077"
    },
    {
      "type": "WEB",
      "url": "https://github.com/remix-run/react-router/commit/59811921d3c7d599077b8cadccdcd65a233165e0"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jacob-ebey/turbo-stream/blob/v2.4.1/src/flatten.ts#L175-L177"
    },
    {
      "type": "WEB",
      "url": "https://github.com/jacob-ebey/turbo-stream/blob/v2.4.1/src/unflatten.ts#L185-L189"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/remix-run/react-router"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "React Router vulnerable to Denial of Service via reflected user input in single-fetch"
}

CVE-2026-34077 (GCVE-0-2026-34077)

Vulnerability from cvelistv5 – Published: 2026-06-02 17:31 – Updated: 2026-06-03 13:19

Title

React Router vulnerable to Denial of Service via reflected user input in single-fetch

Summary

React Router is a router for React. In versions 7.7.0 through 7.13.1, when using React Router's unstable React Server Components (RSC) APIs, there is a potential client-side Cross-Site Scripting (XSS) vulnerability in the RSC redirect handling if redirects come from untrusted sources. This does not impact applications that are not using the unstable RSC APIs in React Router. This is patched in version 7.13.2.

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-03 13:18 UTC

CWE

CWE-770 - Allocation of Resources Without Limits or Throttling

Assigner

GitHub_M mitre root

References

1 reference

URL	Tags
https://github.com/remix-run/react-router/securit…	x_refsource_CONFIRM

Impacted products

2 products

Vendor	Product	Version
remix-run	react-router	Affected: >= 7.0.0, < 7.14.0
remix-run	turbo-stream	Affected: < 3.0.0

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-34077",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-03T13:18:47.056106Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-03T13:19:02.279Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "react-router",
          "vendor": "remix-run",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 7.0.0, \u003c 7.14.0"
            }
          ]
        },
        {
          "product": "turbo-stream",
          "vendor": "remix-run",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 3.0.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "React Router is a router for React. In versions 7.7.0 through 7.13.1, when using React Router\u0027s unstable React Server Components (RSC) APIs, there is a potential client-side Cross-Site Scripting (XSS) vulnerability in the RSC redirect handling if redirects come from untrusted sources. This does not impact applications that are not using the unstable RSC APIs in React Router. This is patched in version 7.13.2."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-770",
              "description": "CWE-770: Allocation of Resources Without Limits or Throttling",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-02T17:31:35.579Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/remix-run/react-router/security/advisories/GHSA-rxv8-25v2-qmq8",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/remix-run/react-router/security/advisories/GHSA-rxv8-25v2-qmq8"
        }
      ],
      "source": {
        "advisory": "GHSA-rxv8-25v2-qmq8",
        "discovery": "UNKNOWN"
      },
      "title": "React Router vulnerable to Denial of Service via reflected user input in single-fetch"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-34077",
    "datePublished": "2026-06-02T17:31:35.579Z",
    "dateReserved": "2026-03-25T16:21:40.868Z",
    "dateUpdated": "2026-06-03T13:19:02.279Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.