Automatic text replacement let users spoof URLs ending in x, like netflix.com.

Elon Musk’s clumsy brand shift from Twitter to X caused a potentially big problem this week when the social network started automatically changing “twitter.com” to “x.com” in links. The automatic text replacement reportedly applied to any URL ending in “twitter.com” even if it wasn’t actually a twitter.com link.

The change apparently went live on X’s app for iOS, but not on the web version. It seems to have been a problem for a day or two before the company fixed the automatic text replacement so that it wouldn’t affect non-Twitter.com domains.

Security reporter Brian Krebs called the move “a gift to phishers” in an article yesterday. It was a phishing risk because scammers could register a domain name like “netflitwitter.com,” which would appear as “netflix.com” in posts on X, but clicking the link would take a user to netflitwitter.com.

“A search at DomainTools.com shows at least 60 domain names have been registered over the past two days for domains ending in ‘twitter.com,’ although research so far shows the majority of these domains have been registered ‘defensively’ by private individuals to prevent the domains from being purchased by scammers,” Krebs wrote.