CVE-2026-49843CWE-287

FreeSWITCH: Pre-authentication session eviction via attacker-chosen `sessid` in `mod_verto`

Medium · published June 9, 2026

CVSS v3.1
5.3
EPSS
1%
Percentile
42.1
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, mod_verto's JSON-RPC handler bound the connection to the client-supplied sessid on the first frame, before the authentication gate. Binding inserts the connection into the global session hash and, on a key collision, drops the prior occupant of that slot — sending it a verto.punt, detaching its calls, and closing its socket. An unauthenticated network attacker who knows a target session UUID could therefore evict the legitimate client. This issue has been patched in version 1.11.1.

The record
Technical detail
CVSS v3.1
5.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CVSS v4.0
Not supplied
EPSS
0.00503 · 42.1th percentile
Weakness
CWE-287 · Improper Authentication
Published
2026-06-09T16:04Z
EPSS history
Timeline
  • 09 JUN 16:04Z
    FreeSWITCH: Pre-authentication session eviction via attacker-chosen `sessid` in `mod_verto`
    cvelistv5