BTCPay Server 1.3.0 through 1.5.3 allows a remote attacker to obtain sensitive information when a public Point of Sale app is exposed. The sensitive information, found in the HTML source code, includes the xpub of the store. Also, if the store isn't using the internal lightning node, the credentials of a lightning node are exposed.
BTCPay Server through 1.0.7.0 suffers from directory traversal, which allows an attacker with admin privileges to achieve code execution. The attacker must craft a malicious plugin file with special characters to upload the file outside of the restricted directory.