Stack-based buffer overflow in freeswitch - CVE-2026-116567
Published: November 9, 2026
Vulnerability identifier: #VU162784
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-116567
CWE-ID: CWE-121
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows an unauthenticated remote attacker to crash FreeSWITCH and terminate all active calls when the non-default mod_rtmp module is built and loaded.
The vulnerability exists due to an unchecked write into a fixed stack buffer when mod_rtmp renders an oversized RTMP user-control message body as hexadecimal text. An unauthenticated remote attacker can send a single crafted control message to the reachable RTMP listener before login to trigger the overflow.
Affected software
freeswitch
How to mitigate CVE-2026-116567
Install security update from vendor's website.
freeswitch - update to 1.11.2