{"answers":{"affected":"4 open source packages ship an affected version, including @remix-run/react and react-router. It affects 2 products.","exploited":"There is no known exploitation of CVE-2026-21884 in the wild and no public exploit code.","fix":"Upgrade @remix-run/react to 2.17.3 or later.","what":"CVE-2026-21884 is a high-severity cross-site scripting vulnerability in remix-run react-router, published on 10 Jan 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link."},"fix_prompt":"Check this codebase for CVE-2026-21884 and fix it if it is affected.\n\nWhat it is: CVE-2026-21884 is a high-severity cross-site scripting vulnerability in remix-run react-router, published on 10 Jan 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.\nExploitation: There is no known exploitation of CVE-2026-21884 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- @remix-run/react (npm): affected all versions; fixed in 2.17.3\n- @remix-run/react (npm): affected all versions; fixed in 2.17.3\n- react-router (npm): affected from 7.0.0; fixed in 7.12.0\n- react-router (npm): affected from 7.0.0; fixed in 7.12.0\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-21884/ (Markdown: https://insights.sbomify.com/CVE-2026-21884/index.md)","id":"CVE-2026-21884","markdown":"https://insights.sbomify.com/CVE-2026-21884/index.md","name":"CVE-2026-21884","record":{"aliases":["GHSA-8v8x-cx79-35w7","ROOT-APP-NPM-CVE-2026-21884"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["code_execution"],"network_reachable":"yes","non_default_config":true,"product_category":"React Router library","requires_auth":"none","summary":"Attackers can execute arbitrary JavaScript during server-side rendering if untrusted content generates ScrollRestoration keys in Framework Mode.","user_interaction":"required","vuln_class":"xss"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[{"product":"react-router","vendor":"shopify"},{"product":"remix-run\\/react","vendor":"shopify"}],"cvss":{"score":8.2,"severity":"high","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N","version":"3.1"},"cwes":[{"id":"CWE-79","name":"Improper Neutralization of Input During Web Page Generation"}],"description":"React Router is a router for React. In @remix-run/react version prior to 2.17.3. and react-router 7.0.0 through 7.11.0, a XSS vulnerability exists in in React Router's \u003cScrollRestoration\u003e API in Framework Mode when using the getKey/storageKey props during Server-Side Rendering which could allow arbitrary JavaScript execution during SSR if untrusted content is used to generate the keys. There is no impact if server-side rendering in Framework Mode is disabled, or if Declarative Mode (\u003cBrowserRouter\u003e) or Data Mode (createBrowserRouter/\u003cRouterProvider\u003e) is being used. This issue has been patched in @remix-run/react version 2.17.3 and react-router version 7.12.0.","ecosystems":["npm"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"React Router SSR XSS in ScrollRestoration","id":"CVE-2026-21884","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"npm","product":null,"products":[],"type":"xss","year":"2026"},"n_packages":4,"n_references":1,"next":{"headline":"Miniflux Media Proxy SSRF via /proxy endpoint allows access to internal network resources","id":"CVE-2026-21885"},"packages":[{"ecosystem":"npm","fixed":["2.17.3"],"introduced":["0"],"last_affected":[],"package":"@remix-run/react","purl":null,"source":"GHSA-8v8x-cx79-35w7"},{"ecosystem":"npm","fixed":["2.17.3"],"introduced":["0"],"last_affected":[],"package":"@remix-run/react","purl":"pkg:npm/%40remix-run/react","source":"GHSA-8v8x-cx79-35w7"},{"ecosystem":"npm","fixed":["7.12.0"],"introduced":["7.0.0"],"last_affected":[],"package":"react-router","purl":null,"source":"GHSA-8v8x-cx79-35w7"},{"ecosystem":"npm","fixed":["7.12.0"],"introduced":["7.0.0"],"last_affected":[],"package":"react-router","purl":"pkg:npm/react-router","source":"GHSA-8v8x-cx79-35w7"}],"prev":{"headline":"Bokeh server applications have Incomplete Origin Validation in WebSockets","id":"CVE-2026-21883"},"products":["react-router"],"published":"2026-01-10","related":[{"cvss_score":8.7,"headline":"React Router: Unauthenticated Denial of Service via Inefficient Route Matching","id":"CVE-2026-55685","kev_date_added":null,"published":"2026-07-27"},{"cvss_score":8.1,"headline":"React Router's vendored turbo-stream v2 allows arbitrary constructor invocation via TYPE_ERROR deserialization leading to Unauth RCE","id":"CVE-2026-42211","kev_date_added":null,"published":"2026-06-02"},{"cvss_score":8,"headline":"React Router vulnerable to XSS in unstable RSC redirect handling via javascript: redirect targets","id":"CVE-2026-33245","kev_date_added":null,"published":"2026-06-02"},{"cvss_score":8,"headline":"React Router vulnerable to XSS via Open Redirects","id":"CVE-2026-22029","kev_date_added":null,"published":"2026-01-10"},{"cvss_score":7.6,"headline":"React Router has XSS Vulnerability","id":"CVE-2025-59057","kev_date_added":null,"published":"2026-01-10"},{"cvss_score":7.5,"headline":"React Router vulnerable to Denial of Service via reflected user input in single-fetch","id":"CVE-2026-34077","kev_date_added":null,"published":"2026-06-02"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-07-15","vendors":["remix-run"]},"summary":"Attackers can execute arbitrary JavaScript during server-side rendering if untrusted content generates ScrollRestoration keys in Framework Mode.","url":"https://insights.sbomify.com/CVE-2026-21884/"}