---
id: "CVE-2026-116572"
kind: "vulnerability"
aliases: ["CVE-2026-116572"]
title: "FreeSWITCH: long SIP display name overflows stack, crashing the telephony server"
severity: "medium"
cvss: 6.5
epss: null
exploited: false
status: "open"
category: "runtime"
products: []
ecosystems: []
tags: ["freeswitch", "runtime", "sip", "telephony", "voip"]
not_affected_if: ["auth-required", "presence-disabled", "version-outside-1.10.0-to-1.11.1"]
published_at: "2026-11-05T20:17:44+00:00"
first_seen_at: "2026-11-05T20:40:45+00:00"
updated_at: "2026-11-05T20:43:18+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-116572", "first_seen_at": "2026-11-05T20:40:45+00:00"}]
exploit_sources: []
---

# FreeSWITCH: long SIP display name overflows stack, crashing the telephony server

FreeSWITCH's mod_sofia module copies a SIP Contact display name into a fixed 512-byte stack buffer when sending dialog-event notifications, so an oversized name overflows it. A peer can crash the FreeSWITCH process and drop all active calls, and the overflow may allow more than a crash.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Run `fs_cli -x "version"` or check the installed FreeSWITCH version and see whether it is in the range 1.10.0 to 1.11.1.
- Check whether presence management (mod_sofia presence, shared appearance) is enabled in the SIP profile configuration.
- Check whether subscription authentication is disabled in the SIP profile.

## Fix

- FreeSWITCH `1.11.2` (fixed version stated in the description; the range is 1.10.0 to 1.11.1)

## Timeline

- 2026-11-05T20:40:45+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-116572

## Documents

- [advisory] Vendor advisory: github.com https://github.com/signalwire/freeswitch/security/advisories/GHSA-xrp9-7wv5-xr8c
- [fix] Patch: github.com https://github.com/signalwire/freeswitch/commit/21d8a78fbcdb303f9bb03155631a2ed963fdca8a
- [fix] Release notes: github.com https://github.com/signalwire/freeswitch/releases/tag/v1.11.2

## From the sources

FreeSWITCH is an open-source software telecommunications platform. From 1.10.0 to 1.11.1, there is a stack-based buffer overflow in  mod_sofia  when processing SIP Contact display names for dialog-event notifications. A peer can establish a dialog containing an excessively long display name and subsequently subscribe to that entity’s dialog events, causing the stored value to overflow a fixed 512-byte stack buffer. Exploitation requires presence management to be enabled, directly or through shared appearance, and normally requires valid profile credentials unless subscription authentication is disabled. The overflow can terminate the FreeSWITCH process and all active calls. This vulnerability is fixed in version 1.11.2.

---

_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_