Quassel before 0.12.2 does not properly re-initialize the database session when the PostgreSQL database is restarted, which allows remote attackers to conduct SQL injection attacks via a \ (backslash) in a message. NOTE: this vulnerability exists because of an incomplete fix for CVE-2013-4422.
Improper Neutralization of Special Elements used in an SQL Command The product constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component. Without sufficient removal or quoting of SQL syntax in user-controllable inputs, the generated SQL query can cause those inputs to be interpreted as SQL instead of ordinary user data.