Epiphany 2.28 and 2.29, when WebKit and LibSoup are used, unconditionally displays a closed-lock icon for any URL beginning with the https: substring, without any warning to the user, which allows man-in-the-middle attackers to spoof arbitrary https web sites via a crafted X.509 server certificate.
Untrusted search path vulnerability in the Python interface in Epiphany 2.22.3, and possibly other versions, allows local users to execute arbitrary code via a Trojan horse Python file in the current working directory, related to a vulnerability in the PySys_SetArgv function (CVE-2008-5983).
The International Domain Name (IDN) support in Epiphany allows remote attackers to spoof domain names using punycode encoded domain names that are decoded in URLs and SSL certificates in a way that uses homograph characters from other character sets, which facilitates phishing attacks.