CVE-2016-2145: The am_read_post_data function in mod_auth_mellon before 0.11.1 does not check if the ap_get_client_block function returns an error, which allows remote attackers to cause a denial of service (segmentation fault and process crash) via a crafted POST data.
CVE-2016-2146: The am_read_post_data function in mod_auth_mellon before 0.11.1 does not limit the amount of data read, which allows remote attackers to cause a denial of service (worker process crash, web server deadlock, or memory consumption) via a large amount of POST data.
CVE-2019-3877: A vulnerability was found in mod_auth_mellon before v0.14.2. An open redirect in the logout URL allows requests with backslashes to pass through by assuming that it is a relative URL, while the browsers silently convert backslash characters into forward slashes treating them as an absolute URL. This mismatch allows an attacker to bypass the redirect URL validation logic in apr_uri_parse function.
CVE-2019-13038: mod_auth_mellon through 0.14.2 has an Open Redirect via the login?ReturnTo= substring, as demonstrated by omitting the // after http: in the target URL.
CVE-2017-6807: mod_auth_mellon before 0.13.1 is vulnerable to a Cross-Site Session Transfer attack, where a user with access to one web site running on a server can copy their session cookie to a different web site on the same server to get access to that site.