CVE-2026-49847CWE-674

FreeSWITCH: Stack overflow in bundled cJSON parser via deeply nested JSON

High · published June 9, 2026

CVSS v3.1
7.5
EPSS
1%
Percentile
44.2
In the wild
Unconfirmed
What it is

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 version 1.11.1, a single unauthenticated WebSocket frame containing a deeply nested JSON document crashes the FreeSWITCH process via stack overflow, terminating all calls and sessions on the host. The recursion drives the worker thread's stack pointer into the stack guard page, raising SIGSEGV from the kernel before any usable write primitive develops. This issue has been patched in version 1.11.1.

The record
Technical detail
CVSS v3.1
7.5 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.00533 · 44.2th percentile
Weakness
CWE-674 · Uncontrolled Recursion
Published
2026-06-09T16:05Z
EPSS history
Timeline
  • 09 JUN 16:05Z
    FreeSWITCH: Stack overflow in bundled cJSON parser via deeply nested JSON
    cvelistv5