Severity: Critical
CVSS Score: 9.3
The nsSOCKSSocketInfo::ConnectToProxy function in Mozilla Firefox before 18.0, Firefox ESR 17.x before 17.0.2, Thunderbird before 17.0.2, Thunderbird ESR 17.x before 17.0.2, and SeaMonkey before 2.15 does not ensure thread safety for SSL sessions, which allows remote attackers to execute arbitrary code via crafted data, as demonstrated by e-mail message data.