GHSA-fg5q-r2q5-qmh3 — drupal/core
MEDIUMGHSA-fg5q-r2q5-qmh3 is a medium-severity (CVSS 5.9) vulnerability in drupal/core. A fix is available for drupal/core — see the affected versions and patch details below.
Drupal CRLF injection vulnerability in the drupal_set_header function
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-fg5q-r2q5-qmh3 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
drupal/core🐘drupal/drupalReal-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
CRLF injection vulnerability in the drupal_set_header function in Drupal 6.x before 6.38, when used with PHP before 5.1.2, allows remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks by leveraging a module that allows user-submitted data to appear in HTTP headers.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | drupal/core | ≥ 6.0&&< 6.38 | 6.38composer require drupal/core:^6.38 |
| 🐘Packagist | drupal/drupal | ≥ 6.0&&< 6.38 | 6.38composer require drupal/drupal:^6.38 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for drupal/core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update drupal/core to 6.38 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-fg5q-r2q5-qmh3 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-fg5q-r2q5-qmh3 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-fg5q-r2q5-qmh3. 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-fg5q-r2q5-qmh3 in your dependencies?
O3 Security finds GHSA-fg5q-r2q5-qmh3 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.