Open Redirect in next (CVE-2021-37699)
Summary
Vulnerability in next (CVE-2021-37699). Confidential information can be exposed externally. Exploitable via getInitialProps. Mitigation: upgrade to 11.1.0 or later.
Original description
The description as published by the source.
Next.js is an open source website development framework to be used with the React library. In affected versions specially encoded paths could be used when pages/_error.js was statically generated, allowing an open redirect to occur to an external site. In general, this redirect does not directly harm users although it can allow for phishing attacks by redirecting to an attacker's domain from a trusted domain.
Impact
- Affected: Users of Next.js between
10.0.5and10.2.0 - Affected: Users of Next.js between
11.0.0and11.0.1usingpages/_error.jswithoutgetInitialProps - Affected: Users of Next.js between
11.0.0and11.0.1usingpages/_error.jsandnext export - Not affected: Deployments on Vercel (vercel.com) are not affected
- Not affected: Deployments with
pages/404.js - Note that versions prior to 0.9.9 package
nextnpm package hosted a different utility (0.4.1 being the latest version of that codebase), and this advisory does not apply to those versions.
We recommend upgrading to the latest version of Next.js to improve the overall security of your application.
Patches
Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory OSV
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2021-37699 has been found in next.
Attackers can target a specific entry point like getInitialProps over the network to misuse the product.
Confidential information can be exposed externally.
What to do: upgrade next to 11.1.0 or later.
If unsure, ask your IT team or search "next CVE-2021-37699" on the vendor's site.
CVE-2021-37699 (next) — CWE-601
Attack vector: remote (network-reachable) / unauthenticated
Attack surface: getInitialProps / next
Patched: 11.1.0 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-601) exists in next. Attackers reach the vulnerable code path via getInitialProps without authentication.
Check the vendor advisory for the affected versions of next. Attack surface: getInitialProps / next.
Severity: ?. Confidential information can be exposed externally.
Update to 11.1.0.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'next' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'next' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
nextを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade next to 11.1.0ステージング環境で 11.1.0 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory nvd.nist.gov
- package github.com
- web github.com
- web github.com