Summary
FreeSWITCH is a Software Defined Telecom Stack enabling the digital transformation from proprietary telecom switches to a software implementation that runs on any commodity hardware. Prior to 1.11.2, rtmp_i_connect() passed the first RTMP connect argument to amf0_object_get() without checking whether the AMF value was an object. A string or number in place of an AMF object caused union bytes from the message to be interpreted as node pointers and dereferenced. Any client with network access to an enabled mod_rtmp listener could send the malformed connect command before login; the module is disabled in the stock build and configuration. The invalid read reliably crashes FreeSWITCH and ends every active call, while no write, memory disclosure, or code execution has been demonstrated. This issue is fixed in version 1.11.2.