Editing URL redirection (section)

==Security issues==

URL redirection can be abused by attackers to perform [[phishing]] attacks. If a redirect target is not sufficiently validated by a web application, an attacker can make a web application redirect to an arbitrary website. This vulnerability is known as an open-redirect vulnerability.<ref name=":0">{{Cite book |last1=Innocenti |first1=Tommaso |last2=Golinelli |first2=Matteo |last3=Onarlioglu |first3=Kaan |last4=Mirheidari |first4=Ali |last5=Crispo |first5=Bruno |last6=Kirda |first6=Engin |chapter=OAuth 2.0 Redirect URI Validation Falls Short, Literally |date=2023-12-04 |title=Annual Computer Security Applications Conference |chapter-url=https://dl.acm.org/doi/10.1145/3627106.3627140 |series=ACSAC '23 |location=New York, NY, USA |publisher=Association for Computing Machinery |pages=256–267 |doi=10.1145/3627106.3627140 |isbn=979-8-4007-0886-2|hdl=11572/399070 |hdl-access=free }}</ref><ref name="Open_Redirect"/> In certain cases when an open redirect occurs as part of an [[authentication]] flow, the vulnerability is known as a covert redirect.<ref name="Covert_Redirect" /><ref name="CNET" /> When a covert redirect occurs, the attacker website can steal [[Authentication cookie|authentication information]] from the victim website.<ref name=":0" /> Open redirect vulnerabilities are fairly common on the web. In June 2022, TechRadar found over 25 active examples of open redirect vulnerabilities on the web, including sites like [[Google]] and [[Instagram]].<ref>{{Cite web |author1=Mike Williams |date=2022-06-05 |title=What is an Open Redirect vulnerability, why is it dangerous and how can you stay safe? |url=https://www.techradar.com/features/what-is-open-redirect-vulnerability |access-date=2024-04-08 |website=TechRadar |language=en}}</ref> Open redirects have their own CWE identifier, CWE-601.<ref>{{Cite web |title=CWE - CWE-601: URL Redirection to Untrusted Site ('Open Redirect') (4.14) |url=https://cwe.mitre.org/data/definitions/601.html |access-date=2024-04-08 |website=cwe.mitre.org}}</ref>

URL redirection also provides a mechanism to perform [[cross-site leak]] attacks. By timing how long a website took to return a particular page or by differentiating one destination page from another, an attacker can gain significant information about another website's state. In 2021, Knittel et al. discovered a vulnerability in the Chrome's Performance API implementation which allowed them to reliably detect cross-origin redirects.<ref>{{Cite book |last1=Knittel |first1=Lukas |last2=Mainka |first2=Christian |last3=Niemietz |first3=Marcus |last4=Noß |first4=Dominik Trevor |last5=Schwenk |first5=Jörg |chapter=XSinator.com: From a Formal Model to the Automatic Evaluation of Cross-Site Leaks in Web Browsers |date=2021-11-13 |title=Proceedings of the 2021 ACM SIGSAC Conference on Computer and Communications Security |chapter-url=https://dl.acm.org/doi/10.1145/3460120.3484739 |series=CCS '21 |location=New York, NY, USA |publisher=Association for Computing Machinery |pages=1771–1788 |doi=10.1145/3460120.3484739 |isbn=978-1-4503-8454-4}}</ref>