CVE-2021-41105

Name of the Vulnerable Software and Affected Versions FreeSWITCH versions prior to 1.10.7

Description The issue allows remote attackers to terminate calls by flooding a media port handling SRTP traffic with specially crafted SRTP packets, leading to denial of service. This can be done continuously, denying encrypted calls during the attack. The call disconnection occurs due to a hard-coded threshold of 100 SRTP errors in the source file switch rtp.c. The attack does not require authentication or any special foothold in the caller's or the callee's network. This issue was reproduced in both SIP and WebRTC environments using the SDES and DTLS key exchange mechanisms, respectively.

Recommendations For versions prior to 1.10.7, update to version 1.10.7 to resolve the issue. As a temporary workaround, consider restricting access to the switch rtp.c file or disabling the SRTP functionality until a patch is applied. Avoid using the SRTP protocol in sensitive environments until the issue is resolved.