Brute Force Authentication Tags of CookieStore Sessions in Auth0-PHP SDKGHSA-g98g-r7gf-2r25
CRITICALFix: auth0/auth0-PHP@52a7948GHSA-g98g-r7gf-2r25 is a critical-severity (CVSS 9.1) Improper Authentication vulnerability in auth0/auth0-php. A fix is available for auth0/auth0-php — see the affected versions and patch details below.
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-g98g-r7gf-2r25.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
auth0/auth0-phpReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
Overview Session cookies of applications using the Auth0-PHP SDK configured with CookieStore have authentication tags that can be brute forced, which may result in unauthorized access.
Am I Affected? You are affected by this vulnerability if you meet the following pre-conditions:
- Applications using the Auth0-PHP SDK, or the following SDKs that rely on the Auth0-PHP SDK: a. Auth0/symfony, b. Auth0/laravel-auth0, c. Auth0/wordpress,
- Session storage configured with CookieStore.
Fix Upgrade Auth0/Auth0-PHP to v8.14.0. As an additional precautionary measure, we recommend rotating your cookie encryption keys. Note that once updated, any previous session cookies will be rejected.
Acknowledgement Okta would like to thank Félix Charette for discovering this vulnerability.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | auth0/auth0-php | ≥ 8.0.0-BETA1&&< 8.14.0 | 8.14.0composer require auth0/auth0-php:^8.14.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for auth0/auth0-php, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update auth0/auth0-php to 8.14.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-g98g-r7gf-2r25 is resolved across your whole dependency graph.
Workarounds
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.
Frequently Asked Questions
Is GHSA-g98g-r7gf-2r25 in your dependencies?
Find it across Packagist, including transitive dependencies.