Описание
php-svg-lib lacks path validation on font through SVG inline styles
Summary
php-svg-lib fails to validate that font-family doesn't contain a PHAR url, which might leads to RCE on PHP < 8.0, and doesn't validate if external references are allowed. This might leads to bypass of restrictions or RCE on projects that are using it, if they do not strictly revalidate the fontName that is passed by php-svg-lib.
Details
The Style::fromAttributes(), or the Style::parseCssStyle() should check the content of the font-family and prevents it to use a PHAR url, to avoid passing an invalid and dangerous fontName value to other libraries. The same check as done in the Style::fromStyleSheets might be reused :
PoC
Parsing the following SVG :
will pass the phar:///path/to/whatever.phar/blaklis as $family in SurfaceCpdf::setFont, which is then passed to the canvas selectFont as a $fontName.
Impact
Libraries using this library as a dependency might be vulnerable to some bypass of restrictions, or even RCE, if they do not double check the value of the fontName that is passed by php-svg-lib
Ссылки
Пакеты
phenx/php-svg-lib
< 0.5.2
0.5.2
Связанные уязвимости
php-svg-lib is a scalable vector graphics (SVG) file parsing/rendering library. Prior to version 0.5.2, php-svg-lib fails to validate that font-family doesn't contain a PHAR url, which might leads to RCE on PHP < 8.0, and doesn't validate if external references are allowed. This might leads to bypass of restrictions or RCE on projects that are using it, if they do not strictly revalidate the fontName that is passed by php-svg-lib. The `Style::fromAttributes(`), or the `Style::parseCssStyle()` should check the content of the `font-family` and prevents it to use a PHAR url, to avoid passing an invalid and dangerous `fontName` value to other libraries. The same check as done in the `Style::fromStyleSheets` might be reused. Libraries using this library as a dependency might be vulnerable to some bypass of restrictions, or even remote code execution, if they do not double check the value of the `fontName` that is passed by php-svg-lib. Version 0.5.2 contains a fix for this issue.
php-svg-lib is a scalable vector graphics (SVG) file parsing/rendering ...
Уязвимость библиотеки анализа и рендеринга файлов векторной графики php-svg-lib, связанная с некорректным внешним управлением именем или путем файла, позволяющая нарушителю выполнить произвольный код