# CVE-2026-73419: NextAuth.js: OAuth state, nonce, and PKCE check cookies are not bound to the provider that created them > Attackers can link their account to a victim's profile in multi-provider NextAuth.js apps, gaining persistent access to the victim's account. - **Severity:** Medium 6.8 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** A user has to click or open something - **Fix available:** Yes - **Published:** 12 Aug 2026 - **Updated:** 13 Aug 2026 - **Also known as:** CLEANSTART-2026-HJ83512, CLEANSTART-2026-JW21689, ECHO-4bf4-a83a-db7c, GHSA-x445-f3h2-j279, MINI-97pm-49wj-qr65 ## What is CVE-2026-73419? CVE-2026-73419 is a medium-severity authentication bypass vulnerability in @auth core, published on 12 Aug 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link. ### Official description NextAuth.js provides authentication for Next.js. Prior to@auth/core 0.41.3 and next-auth 4.24.15 and 5.0.0-beta.32, Auth.js stores the OAuth/OIDC anti-CSRF checks state, nonce, and the PKCE verifier in global cookies that are not bound to the provider that created them. On callback, a check value minted during a sign-in started with one provider can satisfy the callback for a different provider because the stored cookie is not verified against the callback provider's identity, including the provider ID, issuer, client ID, or redirect URI. In a multi-provider application that permits account linking while logged in, when one provider's authorization request is observable and a target provider callback can be satisfied without a PKCE verifier, an attacker can lure a victim into starting a legitimate same-origin flow and link the attacker's target-provider account to the victim's Auth.js user. The linked provider grants the attacker persistent sign-in to the victim's account, while cross-site request forgery alone is insufficient. This issue is fixed in @auth/core 0.41.3 and next-auth 4.24.15 and 5.0.0-beta.32. Weakness: CWE-940 (Improper Verification of Source of a Communication Channel), CWE-346 (Origin Validation Error), CWE-345 (Insufficient Verification of Data Authenticity) ## Which versions are affected by CVE-2026-73419? 6 open source packages ship an affected version, including @auth/core and next-auth. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `@auth/core` | npm | All versions | 0.41.3 | | `@auth/core` | npm | All versions | 0.41.3 | | `next-auth` | npm | All versions | 4.24.15 | | `next-auth` | npm | All versions | 4.24.15 | | `next-auth` | npm | From 5.0.0-beta.1 | 5.0.0-beta.32 | | `next-auth` | npm | From 5.0.0-beta.1 | 5.0.0-beta.32 | ## How do I fix CVE-2026-73419? Upgrade @auth/core to 0.41.3 or later. ## Is CVE-2026-73419 being exploited? There is no known exploitation of CVE-2026-73419 in the wild and no public exploit code. ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-73419 and fix it if it is affected. What it is: CVE-2026-73419 is a medium-severity authentication bypass vulnerability in @auth core, published on 12 Aug 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link. Exploitation: There is no known exploitation of CVE-2026-73419 in the wild and no public exploit code. Affected packages and fixed versions: - @auth/core (npm): affected all versions; fixed in 0.41.3 - @auth/core (npm): affected all versions; fixed in 0.41.3 - next-auth (npm): affected all versions; fixed in 4.24.15 - next-auth (npm): affected all versions; fixed in 4.24.15 - next-auth (npm): affected from 5.0.0-beta.1; fixed in 5.0.0-beta.32 - next-auth (npm): affected from 5.0.0-beta.1; fixed in 5.0.0-beta.32 Task: 1. 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. 2. 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. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2026-73419/ (Markdown: https://insights.sbomify.com/CVE-2026-73419/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-73419 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-73419 - OSV: https://osv.dev/vulnerability/CVE-2026-73419 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-73419/ Summaries are generated and may contain mistakes; the official description above is the record.