Vulnerability in next-auth (CVE-2026-73421)
Summary
Vulnerability in next-auth (CVE-2026-73421). Risk of unauthorized operations or information disclosure. Exploitable via auth. Mitigation: upgrade to 5.0.0-beta.32 or later.
Original description
The description as published by the source.
NextAuth.js provides authentication for Next.js. From next-auth 5.0.0-beta.0 until 5.0.0-beta.32, applications that gate access by checking only for the existence of the auth object returned by the auth() wrapper can fail open when Auth.js has a server configuration error. In middleware, Route Handlers, React Server Components, and other auth() entry points, a non-OK session response is parsed into a truthy error object instead of null, so checks such as !!auth and if (req.auth) evaluate to true for unauthenticated requests. A provider missing both the issuer and authorization endpoint triggers InvalidEndpoints, and an unset AUTH_SECRET or another server configuration error can produce the same behavior. There is no impact while configuration is valid, but after a deployment becomes misconfigured, routes protected only by session existence silently grant access to every visitor. This issue is fixed in next-auth 5.0.0-beta.32.
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
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-2026-73421 has been found in next-auth.
Attackers can target a specific entry point like auth over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: upgrade next-auth to 5.0.0-beta.32 or later.
If unsure, ask your IT team or search "next-auth CVE-2026-73421" on the vendor's site.
CVE-2026-73421 (next-auth) — CWE-285
Attack surface: auth / null / true / issuer
Patched: 5.0.0-beta.32 — 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-285) exists in next-auth. Attackers reach the vulnerable code path via auth.
Check the vendor advisory for the affected versions of next-auth. Attack surface: auth / null / true / issuer.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 5.0.0-beta.32.
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-auth' . 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
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1Identify exposure identify
grep -r 'next-auth' . | 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-auth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-auth to 5.0.0-beta.32ステージング環境で 5.0.0-beta.32 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 github.com
- advisory github.com
- advisory nvd.nist.gov
- package github.com
- patch github.com
- web github.com
- web github.com