Off-by-one in freeswitch - CVE-2026-116574
Published: November 9, 2026
Vulnerability identifier: #VU162777
CSH Severity: Low
CVSS v4: 6 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-116574
CWE-ID: CWE-193
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a low-privileged remote attacker to crash the FreeSWITCH process or corrupt adjacent heap data.
The vulnerability exists due to an off-by-one buffer reservation error in FreeSWITCH's XML serializer when escaping a four-byte UTF-8 sequence at a specific buffer boundary. A low-privileged remote attacker can repeatedly vary text in caller IDs or SIP headers that the deployment serializes into XML to trigger a single-byte NUL overwrite on the heap.
Affected software
freeswitch
How to mitigate CVE-2026-116574
Install security update from vendor's website.
freeswitch - update to 1.11.2