How severe is CVE-2026-42280?

CVE-2026-42280 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.

Is CVE-2026-42280 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-42280?

CVE-2026-42280 affects Auth0 Auth0.js. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-42280?

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.

Does CVE-2026-42280 have an EU (EUVD) identifier?

Yes. CVE-2026-42280 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-32533.

When was CVE-2026-42280 published?

CVE-2026-42280 was published on 2026-05-27 and last updated on 2026-06-17.

CVE-2026-42280

CVE-2026-42280 is a high-severity vulnerability in Auth0 Auth0.js with a CVSS 3.x base score of 7.1. 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-863.

Key facts

Severity: High (CVSS 3.x base score 7.1)
EPSS exploit prediction: 0% (11th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-32533
Weakness: CWE-863
Affected product: Auth0 Auth0.js
Published: 2026-05-27
Last modified: 2026-06-17

Description

Auth0.js is a client-side JavaScript library for Auth0. From 8.11.0 to 9.32.0, under specific preconditions, the Auth0.js SDK may improperly return user profile information using a valid access token when a specifically crafted invalid ID token is provided. This vulnerability is fixed in 10.0.0.

Frequently asked questions

What is CVE-2026-42280?: Auth0.js is a client-side JavaScript library for Auth0. From 8.11.0 to 9.32.0, under specific preconditions, the Auth0.js SDK may improperly return user profile information using a valid access token when a specifically crafted invalid ID token is provided. This vulnerability is fixed in 10.0.0.
How severe is CVE-2026-42280?: CVE-2026-42280 has a CVSS 3.x base score of 7.1, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.
Is CVE-2026-42280 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-42280?: CVE-2026-42280 affects Auth0 Auth0.js. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-42280?: 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.
Does CVE-2026-42280 have an EU (EUVD) identifier?: Yes. CVE-2026-42280 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-32533.
When was CVE-2026-42280 published?: CVE-2026-42280 was published on 2026-05-27 and last updated on 2026-06-17.

References

https://github.com/auth0/auth0.js/security/advisories/GHSA-8qjv-jj2q-x832

Affected products (1)

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

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