knplabs/knp-snappy is a PHP library allowing thumbnail, snapshot or PDF generation from a url or a html page. ## Issue On March 17th the vulnerability CVE-2023-28115 was disclosed, allowing an attacker to gain remote code execution through PHAR deserialization. Version 1.4.2 added a check `if (\strpos($filename, 'phar://') === 0)` in the `prepareOutput` function to resolve this CVE, however if the user is able to control the second parameter of the `generateFromHtml()` function of Snappy, it will then be passed as the `$filename` parameter in the `prepareOutput()` function. In the original vulnerability, a file name with a `phar://` wrapper could be sent to the `fileExists()` function, equivalent to the `file_exists()` PHP function. This allowed users to trigger a deserialization on arbitrary PHAR files. To fix this issue, the string is now passed to the `strpos()` function and if it starts with `phar://`, an exception is raised. However, PHP wrappers being case insensitive, this patch can be bypassed using `PHAR://` instead of `phar://`. A successful exploitation of this vulnerability allows executing arbitrary code and accessing the underlying filesystem. The attacker must be able to upload a file and the server must be running a PHP version prior to 8. This issue has been addressed in commit `d3b742d61a` which has been included in version 1.4.3. Users are advised to upgrade. Users unable to upgrade should ensure that only trusted users may submit data to the `AbstractGenerator->generate(...)` function.

• https://github.com/KnpLabs/snappy/commit/d3b742d61a68bf93866032c2c0a7f1486128b67e
• https://github.com/KnpLabs/snappy/security/advisories/GHSA-92rv-4j2h-8mjj
• https://github.com/KnpLabs/snappy/security/advisories/GHSA-gq6w-q6wh-jggc
• https://github.com/KnpLabs/snappy/commit/d3b742d61a68bf93866032c2c0a7f1486128b67e
• https://github.com/KnpLabs/snappy/security/advisories/GHSA-92rv-4j2h-8mjj
• https://github.com/KnpLabs/snappy/security/advisories/GHSA-gq6w-q6wh-jggc

• Knplabs » Snappy » Version: 0.1.0
  cpe:2.3:a:knplabs:snappy:0.1.0
• Knplabs » Snappy » Version: 0.1.1
  cpe:2.3:a:knplabs:snappy:0.1.1
• Knplabs » Snappy » Version: 0.1.2
  cpe:2.3:a:knplabs:snappy:0.1.2
• Knplabs » Snappy » Version: 0.2.0
  cpe:2.3:a:knplabs:snappy:0.2.0
• Knplabs » Snappy » Version: 0.2.1
  cpe:2.3:a:knplabs:snappy:0.2.1
• Knplabs » Snappy » Version: 0.3.0
  cpe:2.3:a:knplabs:snappy:0.3.0
• Knplabs » Snappy » Version: 0.3.1
  cpe:2.3:a:knplabs:snappy:0.3.1
• Knplabs » Snappy » Version: 0.3.2
  cpe:2.3:a:knplabs:snappy:0.3.2
• Knplabs » Snappy » Version: 0.3.3
  cpe:2.3:a:knplabs:snappy:0.3.3
• Knplabs » Snappy » Version: 0.3.4
  cpe:2.3:a:knplabs:snappy:0.3.4
• Knplabs » Snappy » Version: 0.4
  cpe:2.3:a:knplabs:snappy:0.4
• Knplabs » Snappy » Version: 0.4.1
  cpe:2.3:a:knplabs:snappy:0.4.1
• Knplabs » Snappy » Version: 0.4.2
  cpe:2.3:a:knplabs:snappy:0.4.2
• Knplabs » Snappy » Version: 0.4.3
  cpe:2.3:a:knplabs:snappy:0.4.3
• Knplabs » Snappy » Version: 0.5.0
  cpe:2.3:a:knplabs:snappy:0.5.0
• Knplabs » Snappy » Version: 1.0
  cpe:2.3:a:knplabs:snappy:1.0
• Knplabs » Snappy » Version: 1.0.1
  cpe:2.3:a:knplabs:snappy:1.0.1
• Knplabs » Snappy » Version: 1.0.2
  cpe:2.3:a:knplabs:snappy:1.0.2
• Knplabs » Snappy » Version: 1.0.3
  cpe:2.3:a:knplabs:snappy:1.0.3
• Knplabs » Snappy » Version: 1.0.4
  cpe:2.3:a:knplabs:snappy:1.0.4
• Knplabs » Snappy » Version: 1.1.0
  cpe:2.3:a:knplabs:snappy:1.1.0
• Knplabs » Snappy » Version: 1.2.0
  cpe:2.3:a:knplabs:snappy:1.2.0
• Knplabs » Snappy » Version: 1.2.1
  cpe:2.3:a:knplabs:snappy:1.2.1
• Knplabs » Snappy » Version: 1.3.0
  cpe:2.3:a:knplabs:snappy:1.3.0
• Knplabs » Snappy » Version: 1.3.1
  cpe:2.3:a:knplabs:snappy:1.3.1
• Knplabs » Snappy » Version: 1.4.0
  cpe:2.3:a:knplabs:snappy:1.4.0
• Knplabs » Snappy » Version: 1.4.1
  cpe:2.3:a:knplabs:snappy:1.4.1
• Knplabs » Snappy » Version: 1.4.2
  cpe:2.3:a:knplabs:snappy:1.4.2