CVE-2021-3129 is a critical-severity (CVSS 9.8) remote code execution vulnerability in facade/ignition. It is in CISA's Known Exploited Vulnerabilities catalog (added 2023-09-18) and has been used in ransomware campaigns — treat it as actively exploited and patch now. O3 Security confirms whether CVE-2021-3129 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Unauthenticated remote code execution in Ignition
Exploitation Status
Actively exploited in the wild
- Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2023-09-18 — including use in ransomware campaigns. Federal agencies were required to remediate by 2023-10-09.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2021-3129.
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
CVE-2021-3129 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE sits: patch-first territory.
Where this sits among everything scored
Of 368,770 CVEs with a current EPSS score, this one falls in the ≥ 90% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
facade/ignition🐘facade/ignition🐘facade/ignition🐘facade/ignitionReal-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
Ignition before 2.5.2, as used in Laravel and other products, allows unauthenticated remote attackers to execute arbitrary code because of insecure usage of file_get_contents() and file_put_contents(). This is exploitable on sites using debug mode with Laravel before 8.4.2.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | facade/ignition | ≥ 2.5.0&&< 2.5.2 | 2.5.2 |
| 🐘Packagist | facade/ignition | ≥ 2.0.0&&< 2.4.2 | 2.4.2 |
| 🐘Packagist | facade/ignition | ≥ 1.7.0&&< 1.16.14 | 1.16.14 |
| 🐘Packagist | facade/ignition | all versions | 1.6.15 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Laravel 8.4.2 debug mode - Remote code execution
by SunCSR Team · Jan 14, 2021
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for facade/ignition. 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 facade/ignition to 2.5.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-3129 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 CVE-2021-3129 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 CVE-2021-3129. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2021-3129 in your dependencies?
O3 detects CVE-2021-3129 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.