CVE-2021-3129

Laravel Ignition, the default error-page package bundled with Laravel applications, uses file_get_contents() and file_put_contents() insecurely in its solution-execution feature, allowing unauthenticated remote attackers to read and write arbitrary files on the server. The flaw is triggered by sending a crafted, unauthenticated HTTP request to Ignition's execute-solution endpoint, which is reachable whenever the application runs with debug mode enabled. Attackers can chain the arbitrary file write to execute arbitrary code in the context of the web application, leading to server compromise and, per CISA, ransomware deployment. Any internet-facing Laravel application running a vulnerable version of the Ignition package with debug mode enabled is affected. The vulnerability is known to be exploited in the wild: CISA added it to the Known Exploited Vulnerabilities catalog on 2023-09-18 with ransomware use confirmed, and EPSS assigns it a 99.9% probability of exploitation within 30 days (100th percentile).

What to do: Upgrade facade/ignition to 2.5.2 or later on all Laravel applications, or update to a current Laravel release that bundles the fixed package. Ensure production environments run with debug mode disabled and block or restrict the /_ignition/execute-solution endpoint from untrusted access as an interim mitigation. Given confirmed ransomware use, hunt for signs of compromise such as modified environment files, unexpected scheduled tasks, or webshells, and apply the CISA-required mitigations or discontinue use of the product if patching is not possible.