Denial of Service (DoS)
Affecting commons-fileupload:commons-fileupload artifact, versions [1.3,1.3.2)
commons-fileupload:commons-fileupload provides a simple yet flexible means of adding support for multipart file upload functionality to servlets and web applications.
Affected versions of this package are vulnerable to Denial of Service (DoS) attacks. An attacker can upload a file with a long boundry string in the HTTP header, causing high CPU consumption. The
MultipartStream class contains a flaw that allows remote attackers to cause a Denial of service (CPU consumption) attacks. This happens by setting the length of the multipart boundary to be just below the size of the buffer (4096 bytes) used to read the uploaded file. Typically, the boundary is tens of bytes long, which caused this case to take much longer than usual.
Denial of Service (DoS) describes a family of attacks, all aimed at making a system inaccessible to its intended and legitimate users.
Unlike other vulnerabilities, DoS attacks usually do not aim at breaching security. Rather, they are focused on making websites and services unavailable to genuine users resulting in downtime.
One popular Denial of Service vulnerability is DDoS (a Distributed Denial of Service), an attack that attempts to clog network pipes to the system by generating a large volume of traffic from many machines.
When it comes to open source libraries, DoS vulnerabilities allow attackers to trigger such a crash or crippling of the service by using a flaw either in the application code or from the use of open source libraries.
Two common types of DoS vulnerabilities:
High CPU/Memory Consumption- An attacker sending crafted requests that could cause the system to take a disproportionate amount of time to process. For example, commons-fileupload:commons-fileupload.
Crash - An attacker sending crafted requests that could cause the system to crash. For Example, npm
commons-fileupload:commons-fileupload to version 1.3.2 or higher.