Description

The Imperva Red Team disclosed a cross-site search (XS-Search) vulnerability in the world's largest NFT (non-fungible token) marketplace OpenSea, that can be exploited by an attacker to obtain a user's identity by linking an IP address, an email, or a browser session to a particular NFT, thus accessing a wallet address that would reveal the user's identity. The exploitation begins with the attacker sending a link to the target via SMS or email, which when clicked leaks the device details, IP address, user agent, and software versions. The attacker can then exploit the cross-site search vulnerability to obtain the victim's NFT name and associate the leaked public or NFT wallet address with this identity, such as the phone number or email address to which the link was sent. Moreover, the issue is caused by the iFrame-resizer library's misconfiguration, which the marketplace uses. When this library is used where cross-origin communication isn't restricted by OpeanSea, a cross-site search vulnerability occurs and lets this flaw prevail and leak user identities. If exploited, the attacker can launch targeted phishing attacks, as well as track users who have purchased the highest-value NFTs. However, OpenSea fixed the issue by releasing a patch that restricted cross-origin communication, which mitigated further exploitation of the vulnerability.