Authored by Ivan Fratric, Google Security Research

There is a vulnerability in Kik Messenger for Android that allows an attacker to send arbitrary XMPP stanzas (XMPP control messages) to another Kik client, including XMPP stanzas that are normally sent only by the Kik server. Included is a proof of concept that demonstrates sending of the stc stanza which triggers a captcha dialog and opens an arbitrary attacker-control webpage on the victim client. However, the full impact is likely larger than this, and includes any application features accessible over XMPP.