i failed ccna

i failed ccna.13.3 Types of Vulnerabilities 48113.3 Types of VulnerabilitiesThe ...... Being aware of the flaws and vulnerabilities that exist in a system or network is an important step in fixing them or taking appropriate measures to mitigate the threats they create. Potential vulnerabilities within networks abound, and many of them are caused by 'one or more of the following. Inadequate systems. Design errors. Protocol flaws. Misconfigurations. Software vulnerabilities. Human factors. Malware.Hardware vulnerabilities. Access to network resources in a physical way. Cisco and others have created a database that categorizes threats in the public domain. Common Vulnerability Disclosure(CVE) is a publicly available dictionary of disclosed security vulnerabilities. A casual search with any search engine will direct readers to its official website. In addition, the National Vulnerability Database (NVD) is a standards-based vulnerability repository that can also be quickly searched using a search engine (the NVD URL may change from time to time, so readers are advised to click on any links of interest after performing a search).Several common vulnerabilities are shown below.API abuse: is an attack on vulnerabilities present in application programmable interfaces (APIs).Authentication and authorization circumvention vulnerabilities: attackers can use such vulnerabilities to circumvent the authentication and authorization mechanisms of security systems within the network. Cache overflow: A cache overflow occurs when a program or software places an excessive amount of data into the cache, or when a program attempts to place data in more memory locations than are cached. The attacker creates a cache overflow, with the goal of allowing data outside the boundaries of the allocated memory block to corruptother data, or to crash the program/operating system. In the worst case scenario, it may lead to the execution of malicious code. Cache overflows can occur in a variety of ways, and unfortunately, many of the methods used to prevent cache overflows are not very clever.Cache overflow vulnerabilities typically involve many memory manipulation functions in languages such as C and C++, and programs that call these functions do not perform boundary checks and can easily override the allocated boundaries of such caches. A good example of this is the use of the strncpyO function, which, when used improperly, can lead to a vulnerability.