Описание
The K2 frontend article-save handler accepts an attachment[N][existing] POST field that is concatenated with JPATH_SITE/ and passed to JFile::copy(). JPath::clean does NOT strip .., and there is no allow-list of source paths. An Author can therefore copy configuration.php (or any other file readable by the web user — including ../../../etc/passwd) into /media/k2/attachments/, then retrieve the contents via the K2 attachment-download endpoint.
The K2 frontend article-save handler accepts an attachment[N][existing] POST field that is concatenated with JPATH_SITE/ and passed to JFile::copy(). JPath::clean does NOT strip .., and there is no allow-list of source paths. An Author can therefore copy configuration.php (or any other file readable by the web user — including ../../../etc/passwd) into /media/k2/attachments/, then retrieve the contents via the K2 attachment-download endpoint.
Связанные уязвимости
The K2 frontend article-save handler accepts an `attachment[N][existing]` POST field that is concatenated with `JPATH_SITE/` and passed to `JFile::copy()`. `JPath::clean` does NOT strip `..`, and there is no allow-list of source paths. An Author can therefore copy `configuration.php` (or any other file readable by the web user — including `../../../etc/passwd`) into `/media/k2/attachments/`, then retrieve the contents via the K2 attachment-download endpoint.