Summary
Description
In applications built with the Auth0-PHP SDK, the audience validation in access tokens is performed improperly. Without proper validation, affected applications may accept ID tokens as Access tokens.
Affected product and versions
Projects are affected if they meet the following preconditions:
- Applications using the Auth0 Symfony SDK with versions between 5.0.0 and 5.5.0
- Auth0 Symfony SDK uses the Auth0-PHP SDK with versions between 8.0.0 and 8.17.0.
Resolution
Upgrade Auth0/symfony to version 5.6.0 or greater.
Acknowledgement
Okta would like to thank Jafar Sadiq (iaf4r) for their discovery and responsible disclosure.
Impact
The application does not correctly enforce access controls, allowing a principal to access resources or operations beyond their granted permissions. Typical impact: unauthorized data access or execution of privileged operations.
GHSA-F3R2-88MQ-9V4G has a CVSS score of 6.8 (Medium). The vector is network-reachable, low privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (5.6.0); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Remediation advice
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is GHSA-F3R2-88MQ-9V4G? GHSA-F3R2-88MQ-9V4G is a medium-severity incorrect authorization vulnerability in auth0/symfony (composer), affecting versions >= 5.0.0, <= 5.5.0. It is fixed in 5.6.0. The application does not correctly enforce access controls, allowing a principal to access resources or operations beyond their granted permissions.
- How severe is GHSA-F3R2-88MQ-9V4G? GHSA-F3R2-88MQ-9V4G has a CVSS score of 6.8 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of auth0/symfony are affected by GHSA-F3R2-88MQ-9V4G? auth0/symfony (composer) versions >= 5.0.0, <= 5.5.0 is affected.
- Is there a fix for GHSA-F3R2-88MQ-9V4G? Yes. GHSA-F3R2-88MQ-9V4G is fixed in 5.6.0. Upgrade to this version or later.
- Is GHSA-F3R2-88MQ-9V4G exploitable, and should I be worried? Whether GHSA-F3R2-88MQ-9V4G is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether GHSA-F3R2-88MQ-9V4G is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix GHSA-F3R2-88MQ-9V4G? Upgrade
auth0/symfonyto 5.6.0 or later.