A flaw was found in mod_auth_mellon where it does not sanitize logout URLs properly. This issue could be used by an attacker to facilitate phishing attacks by tricking users into visiting a trusted web application URL that redirects to an external and potentially malicious server. The highest threat from this liability is to confidentiality and integrity.

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.

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.

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.

The mod_auth_mellon module before 0.8.1 allows remote attackers to obtain sensitive information or cause a denial of service (segmentation fault) via unspecified vectors related to a "session overflow" involving "sessions overlapping in memory."

The mod_auth_mellon module before 0.8.1 allows remote attackers to cause a denial of service (Apache HTTP server crash) via a crafted logout request that triggers a read of uninitialized data.