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Glossary: Endpoint, Application and Email Security

directory traversal

Also written: path traversal, ../

An attack that uses ../ sequences, or encoded forms such as %2e%2e%2f, in a file name to reach files outside the intended folder, such as ../../etc/passwd. The fix is to canonicalize the name, then accept it only from an allow list of files or only if it stays inside the permitted folder.

Where the book teaches it

Related terms

canonicalizationallow listinput validation