High severity · published May 27, 2026
CVE-2026-42280
Improper Permission Checking in Auth.js SDK
7.1
CVSS
0.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 11% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AU
auth0.js · auth0
>= 8.11.0 , <= 9.32.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-42280
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-42280
Vendor Advisory
https://github.com/auth0/auth0.js/security/advisories/GHSA-8qjv-jj2q-x832
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7.7
CVE-2020-15125
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7.5
CVE-2017-17068
A cross-origin vulnerability has been discovered in the Auth0 auth0.js library affecting versions < 8.12