Improper Authentication in freeswitch - CVE-2026-49843
Published: June 4, 2026
Vulnerability identifier: #VU133315
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-49843
CWE-ID: CWE-287
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: www.freeswitch.org
Affected software:
freeswitch
freeswitch
Detailed vulnerability description
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to improper authentication in mod_verto JSON-RPC handler when processing the first JSON-RPC frame with a client-supplied sessid. A remote attacker can send a specially crafted request using a known target session UUID to cause a denial of service.
Exploitation requires network reachability to the verto WebSocket listener and prior knowledge of the target session UUID obtained through a side channel. The issue does not allow credential bypass or victim-session takeover.
How to mitigate CVE-2026-49843
Install security update from vendor's website.