GHSA-jjx5-fq5g-8xpc is a high-severity (CVSS 7.5) CWE-310 vulnerability in symfony/security-core. A fix is available for symfony/security-core — see the affected versions and patch details below.
Symfony Cryptographic Vulnerability
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-jjx5-fq5g-8xpc 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 378,567 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-core🐘symfony/security-core🐘symfony/security🐘symfony/security🐘symfony/security🐘symfony/symfony🐘symfony/symfony🐘symfony/symfonyReal-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
The nextBytes function in the SecureRandom class in Symfony before 2.3.37, 2.6.x before 2.6.13, and 2.7.x before 2.7.9 does not properly generate random numbers when used with PHP 5.x without the paragonie/random_compat library and the openssl_random_pseudo_bytes function fails, which makes it easier for attackers to defeat cryptographic protection mechanisms via unspecified vectors.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | symfony/security-core | ≥ 2.4.0&&< 2.6.13 | 2.6.13composer require symfony/security-core:^2.6.13 |
| 🐘Packagist | symfony/security-core | ≥ 2.7.0&&< 2.7.9 | 2.7.9composer require symfony/security-core:^2.7.9 |
| 🐘Packagist | symfony/security | ≥ 2.3.0&&< 2.3.37 | 2.3.37composer require symfony/security:^2.3.37 |
| 🐘Packagist | symfony/security | ≥ 2.4.0&&< 2.6.13 | 2.6.13composer require symfony/security:^2.6.13 |
| 🐘Packagist | symfony/security | ≥ 2.7.0&&< 2.7.9 | 2.7.9composer require symfony/security:^2.7.9 |
| 🐘Packagist | symfony/symfony | ≥ 2.3.0&&< 2.3.37 | 2.3.37composer require symfony/symfony:^2.3.37 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for symfony/security-core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update symfony/security-core to 2.6.13 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-jjx5-fq5g-8xpc 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-jjx5-fq5g-8xpc can be triaged on real exposure rather than presence alone.
Tailored to GHSA-jjx5-fq5g-8xpc. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-jjx5-fq5g-8xpc in your dependencies?
O3 Security finds GHSA-jjx5-fq5g-8xpc across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.