URL Shortener Abuse
The misuse of legitimate URL-shortening services to disguise malicious links, bypassing security filters that check destination URLs.
Also known as: short URL abuse, link cloaking, redirect abuse
Last reviewed: 1 June 2026
URL shorteners like bit.ly, tinyurl.com, and similar services condense long web addresses into compact links. Attackers exploit these services because the shortened link reveals nothing about its final destination — a link that says 'bit.ly/3xYzAbc' could lead anywhere. This allows phishing links, malware downloads, and scam pages to evade email filters and security tools that scan URLs for known malicious domains.
The abuse is especially prevalent in smishing (SMS phishing) where space constraints make short links natural, and in social media posts where platform filters may not follow shortened redirects. Attackers also chain multiple redirects — shortened URL → legitimate redirect service → malicious page — to make analysis harder.
Users can protect themselves by using URL-preview tools (e.g. appending '+' to some shorteners shows the destination) before clicking, and by treating unsolicited short links with heightened suspicion. Organisations can configure email gateways to expand and inspect short links before delivery.
Examples
- A text message claims to be from a postal service and includes a short link; clicking it leads to a fake customs-fee payment page.