Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
Dompdf prior to v1.2.1 allows remote code execution via a .php file in the src:url field of an @font-face Cascading Style Sheets (CSS) statement (within an HTML input file).
CWE-74 - Injection
Listed as the number one web application security risk on the 'OWASP Top Ten', injection attacks are widespread and dangerous, especially in legacy applications. Injection attacks are a class of vulnerabilities in which an attacker injects untrusted data into a web application that gets processed by an interpreter, altering the program's execution. This can result in data loss/theft, loss of data integrity, denial of service, and even compromising the entire system.