A buffer is a data storage area that allows programs that run at different speeds to operate without interfering with each other.
A buffer overrun can happen when someone maliciously accesses the buffer and alters the program’s code, thus changing the function of the program.
Security flaws give hackers access to buffers. A recent example of a buffer overrun was when a digital certificate for SSL (secure socket layer) was found to be inadequate, prompting Microsoft to issue a patch. (SSL is a security protocol for sending messages on the internet and is a component of Internet Explorer and Netscape.) The certificate is required for the internet transmission protocol http (hypertext transfer protocol) to work, but when installed causes a buffer overrun, thus requiring users to install Microsoft’s patch if they want to avoid attacks.
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