GHSA-8535-hvm8-2hmv
Grav is vulnerable to Server-Side Template Injection (SSTI) via Forms
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.
Blast Radius
getgrav/gravReal-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
Summary
Having a simple form on site can reveal the whole Grav configuration details (including plugin configuration details) by using the correct POST payload. Sensitive information may be contained in the configuration details.
PoC
Create a simple form with two fields, 'registration-number' and 'hp'. Add a submit button and set the method to POST(screenshot attached below). Form name set to 'hero-form'. Send a POST request with the following payload and you will notice a response with a php array listing the whole Grav configuration details - including plugins(screenshot attached).
registration-number:d643aaaa
hp:vJyifp
form-name:hero-form
unique_form_id:{{var_dump(_context|slice(0,7))}}
Impact
Server-Side Template (SST) vulnerability. The vulnerability affects the latest Grav version as of 25th of Match 2025 (1.7.48) with all plugins installed (including forms plugin v.7.4.2) to their latest versions as well.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | getgrav/grav | all versions | 1.8.0-beta.27 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for getgrav/grav. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update getgrav/grav to 1.8.0-beta.27 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-8535-hvm8-2hmv 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 pinpoints whether GHSA-8535-hvm8-2hmv is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-8535-hvm8-2hmv. 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-8535-hvm8-2hmv in your dependencies?
O3 detects GHSA-8535-hvm8-2hmv across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.