How severe is CVE-2021-32702?

CVE-2021-32702 has a CVSS 3.x base score of 8.0, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability none.

Is CVE-2021-32702 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-32702?

CVE-2021-32702 affects Auth0 Nextjs-auth0. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-32702?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-32702 published?

CVE-2021-32702 was published on 2021-06-25 and last updated on 2026-06-17.

CVE-2021-32702

CVE-2021-32702 is a high-severity vulnerability in Auth0 Nextjs-auth0 with a CVSS 3.x base score of 8.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: High (CVSS 3.x base score 8.0)
CVSS v2: 4.3
EPSS exploit prediction: 1% (69th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Auth0 Nextjs-auth0
Published: 2021-06-25
Last modified: 2026-06-17

Description

The Auth0 Next.js SDK is a library for implementing user authentication in Next.js applications. Versions before and including `1.4.1` are vulnerable to reflected XSS. An attacker can execute arbitrary code by providing an XSS payload in the `error` query parameter which is then processed by the callback handler as an error message. You are affected by this vulnerability if you are using `@auth0/nextjs-auth0` version `1.4.1` or lower **unless** you are using custom error handling that does not return the error message in an HTML response. Upgrade to version `1.4.1` to resolve. The fix adds basic HTML escaping to the error message and it should not impact your users.

Frequently asked questions

What is CVE-2021-32702?: The Auth0 Next.js SDK is a library for implementing user authentication in Next.js applications. Versions before and including `1.4.1` are vulnerable to reflected XSS. An attacker can execute arbitrary code by providing an XSS payload in the `error` query parameter which is then processed by the callback handler as an error message. You are affected by this vulnerability if you are using `@auth0/nextjs-auth0` version `1.4.1` or lower **unless** you are using custom error handling that does not return the error message in an HTML response. Upgrade to version `1.4.1` to resolve. The fix adds basic HTML escaping to the error message and it should not impact your users.
How severe is CVE-2021-32702?: CVE-2021-32702 has a CVSS 3.x base score of 8.0, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability none.
Is CVE-2021-32702 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-32702?: CVE-2021-32702 affects Auth0 Nextjs-auth0. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-32702?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-32702 published?: CVE-2021-32702 was published on 2021-06-25 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:auth0:nextjs-auth0:*:*:*:*:*:node.js:*:*

More vulnerabilities in Auth0 Nextjs-auth0

CVE-2021-43812 — Medium (CVSS 6.4): The Auth0 Next.js SDK is a library for implementing user authentication in Next.js applications. Versions before 1.6.2…
CVE-2025-67716 — Medium (CVSS 5.7): The Auth0 Next.js SDK is a library for implementing user authentication in Next.js applications. Versions 4.9.0 through…
CVE-2026-40155 — Medium (CVSS 5.4): The Auth0 Next.js SDK is a library for implementing user authentication in Next.js applications. In versions 4.12.0…
CVE-2025-67490 — Medium (CVSS 5.4): The Auth0 Next.js SDK is a library for implementing user authentication in Next.js applications. When using versions…

All CVEs affecting Auth0 Nextjs-auth0 →

Other CWE-79 (Cross-site Scripting (XSS)) vulnerabilities

CVE-2025-49410 — Critical (CVSS 10.0): Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Imran Emu TC…
CVE-2024-47875 — Critical (CVSS 10.0): DOMPurify is a DOM-only, super-fast, uber-tolerant XSS sanitizer for HTML, MathML and SVG. DOMpurify was vulnerable to…
CVE-2024-6886 — Critical (CVSS 10.0): Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Gitea…
CVE-2023-45144 — Critical (CVSS 10.0): com.xwiki.identity-oauth:identity-oauth-ui is a package to aid in building identity and service providers based on…
CVE-2023-45138 — Critical (CVSS 10.0): Change Request is an pplication allowing users to request changes on a wiki without publishing the changes directly.…
CVE-2022-4361 — Critical (CVSS 10.0): Keycloak, an open-source identity and access management solution, has a cross-site scripting (XSS) vulnerability in the…

Browse all CWE-79 (Cross-site Scripting (XSS)) vulnerabilities →