Backend DevelopmentPHP TutorialPHP vulnerability code can implant itself into GIF files_PHP TutorialPHP vulnerability code can implant itself into GIF files_PHP Tutorial
According to a blog post from the Internet Storm Center (ISC) of the SANS Institute, PHP vulnerability code can easily escape website defenses with the help of a legitimate image at the beginning of a GIF file.
SANS Security Blog writes "This is a savvy way to deliver vulnerable code elsewhere, by-passing network security tools without raising alarms or attracting attention at all."
Malicious An attacker can embed vulnerable PHP code into a graphics file. PHP is a programming language often used to open dynamic websites.
Johannes Ullrich, principal researcher at the SANS Institute, said: “Once a malicious GIF file of this type is uploaded to the server, deploying more vulnerable code remotely on the system could cause serious damage. ”
When the user downloads and views the image, the server parses the PHP code and the vulnerable code is executed.
Ullrich said that in the past six months, this technology has popped up mostly on small family websites, and more recently on large photo gallery websites.
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