Critical severity · published Apr 1, 2026
CVE-2026-34236
Auth0 PHP SDK Insufficient Entropy in Cookie Encryption
9.8
CVSS
0.2%
EPSS
No
On KEV
Description
Auth0-PHP is a PHP SDK for Auth0 Authentication and Management APIs. From version 8.0.0 to before version 8.19.0, in applications built with the Auth0 PHP SDK, cookies are encrypted with insufficient entropy, which may result in threat actors brute-forcing the encryption key and forging session cookies. This issue has been patched in version 8.19.0.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 13% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AU
auth0-PHP · auth0
>= 8.0.0, < 8.19.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-34236
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-34236
Product
https://github.com/auth0/auth0-PHP/releases/tag/8.19.0
Vendor Advisory
https://github.com/auth0/auth0-PHP/security/advisories/GHSA-w3wc-44p4-m4j7
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