What is Path Traversal in Phishing?

Path Traversal in Phishing: A technique used to exploit vulnerabilities by manipulating URL paths to access unauthorized directories or files within web applications.

Why It Matters

Path traversal plays a crucial role in phishing campaigns by leveraging the weaknesses in web application infrastructures. This tactic allows attackers to manipulate URLs, potentially exposing sensitive files and data that reside on the server outside of the intended web path. When combined with phishing techniques, this can be particularly dangerous as operators craft their campaigns to redirect potential victims to malicious sites, often covertly attempting to exploit insecure URL implementations.

The inclusion of path traversal in a phishing attack amplifies the potential damage by not only stealing user credentials but also potentially exposing backend files and configurations. Meticulously crafted URL manipulations can deceive users into executing actions that inadvertently grant attackers expanded access or control, making this technique a potent vector in a red team’s arsenal.

In Practice

One example of path traversal in a phishing scenario might involve a phishing email that claims the user needs to verify their account due to suspected fraudulent activity. The email could include a link structured to look legitimate but contains a path traversal payload, such as:


https://example-bank.com/login?redirect=www.example-bank.com/%2E%2E%2F%2E%2E%2Fconfig

Here, the attacker uses encoded path traversal sequences to attempt accessing unauthorized files such as configuration files on the bank’s server, exploiting weak URL redirect validation.

Another example involves a crafted email with a seemingly harmless link to download a necessary security update. Upon clicking, the target would access:


https://secure-update.com/%2E%2E%2F%2E%2E%2Fupdate.exe

This link appears legitimate but points to a location manipulated through path traversal, executing a download of potentially malicious software as part of the guise.

A more subtle attack could employ a URL embedded in a phishing page that tricks administrative users into viewing sensitive directories, where automated scripts parse exposed files for confidential information:


https://targetorganization.com/admin/view?resource=../../../../etc/passwd

When operators craft these engagements, they target web applications that fail to sanitize input paths effectively, taking advantage of URL vulnerabilities documented in resources such as the CISA’s Known Exploited Vulnerabilities Catalog.

Related Terms

Understanding path traversal goes hand-in-hand with concepts like command injection, where attackers exploit input data crafted as commands, cross-site scripting (XSS), involving the insertion of malicious scripts into webpages viewed by other users, and remote file inclusion (RFI), where external files are included and executed on a server.

References

CISA’s Known Exploited Vulnerabilities Catalog

OWASP Path Traversal Guide