title: Snappy vulnerable to PHAR deserialization, allowing remote code execution
description: Snappy is a PHP library allowing thumbnail, snapshot or PDF generation from a url or a html page. Prior to version 1.4.2, Snappy is vulnerable to PHAR deserialization due to a lack of checking on the protocol before passing it into the `file_exists()` function. If an attacker can upload files of any type to the server he can pass in the phar:// protocol to unserialize the uploaded file and instantiate arbitrary PHP objects. This can lead to remote code execution especially when snappy is used with frameworks with documented POP chains like Laravel/Symfony vulnerable developer code. If a user can control the output file from the `generateFromHtml()` function, it will invoke deserialization. This vulnerability is capable of remote code execution if Snappy is used with frameworks or developer code with vulnerable POP chains. It has been fixed in version 1.4.2.
problem types: CWE-502: Deserialization of Untrusted Data
affected:
{
vendor: KnpLabs
product: snappy
versions:
version: < 1.4.2, status: affected
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: HIGH
baseScore: 9.8
baseSeverity: CRITICAL
confidentialityImpact: HIGH
integrityImpact: HIGH
privilegesRequired: NONE
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
version: 3.1
]