GHSA-5pv8-ppvj-4h68 is a medium-severity (CVSS 5.3) Information Exposure vulnerability in symfony/security. A fix is available for symfony/security — see the affected versions and patch details below.
Prevent user enumeration using Guard or the new Authenticator-based Security
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-5pv8-ppvj-4h68 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
symfony/security🐘symfony/security-guard🐘symfony/security-guard🐘symfony/security-guard🐘symfony/security-core🐘symfony/security-core🐘symfony/security-core🐘lexik/jwt-authentication-bundle+9 moreReal-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
Description
The ability to enumerate users was possible without relevant permissions due to different exception messages depending on whether the user existed or not. It was also possible to enumerate users by using a timing attack, by comparing time elapsed when authenticating an existing user and authenticating a non-existing user.
Resolution
We now ensure that 403s are returned whether the user exists or not if the password is invalid or if the user does not exist.
The patch for this issue is available here for branch 3.4.
Credits
I would like to thank James Isaac and Mathias Brodala for reporting the issue and Robin Chalas for fixing the issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | symfony/security | ≥ 5.0.0&&< 5.2.8 | 5.2.8composer require symfony/security:^5.2.8 |
| 🐘Packagist | symfony/security-guard | ≥ 2.8.0&&< 3.4.48 | 3.4.48composer require symfony/security-guard:^3.4.48 |
| 🐘Packagist | symfony/security-guard | ≥ 4.0.0&&< 4.4.23 | 4.4.23composer require symfony/security-guard:^4.4.23 |
| 🐘Packagist | symfony/security-guard | ≥ 5.0.0&&< 5.2.8 | 5.2.8composer require symfony/security-guard:^5.2.8 |
| 🐘Packagist | symfony/security-core | ≥ 2.8.0&&< 3.4.48 | 3.4.48composer require symfony/security-core:^3.4.48 |
| 🐘Packagist | symfony/security-core | ≥ 4.0.0&&< 4.4.23 | 4.4.23composer require symfony/security-core:^4.4.23 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for symfony/security, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update symfony/security to 5.2.8 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-5pv8-ppvj-4h68 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-5pv8-ppvj-4h68 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-5pv8-ppvj-4h68. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
Frequently Asked Questions
Is GHSA-5pv8-ppvj-4h68 in your dependencies?
O3 Security finds GHSA-5pv8-ppvj-4h68 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.