Drupal Reverse Proxy Header allows Manipulating User-Controlled VariablesGHSA-fg8x-q69g-4qp3
MEDIUMGHSA-fg8x-q69g-4qp3 is a medium-severity (CVSS 5.3) CWE-1288 vulnerability in drupal/reverse_proxy_header. A fix is available for drupal/reverse_proxy_header — 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.
- 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-fg8x-q69g-4qp3.
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
drupal/reverse_proxy_headerReal-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
Improper Validation of Consistency within Input vulnerability in Drupal Reverse Proxy Header allows Manipulating User-Controlled Variables. This issue affects Reverse Proxy Header: from 0.0.0 before 1.1.2.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | drupal/reverse_proxy_header | all versions | 1.1.2composer require drupal/reverse_proxy_header:^1.1.2 |
Affected Products
reverse proxy headerreverse_proxy_header_projectDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for drupal/reverse_proxy_header, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update drupal/reverse_proxy_header to 1.1.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-fg8x-q69g-4qp3 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.
Frequently Asked Questions
Is GHSA-fg8x-q69g-4qp3 in your dependencies?
Find it across Packagist, including transitive dependencies.