# CVE-2026-116573: FreeSWITCH mod_sofia stack buffer overflow in dialog notifications

Source: https://junglewise.ai/threats/cve-2026-116573-freeswitch-is-an-open-source-software-telecommunications  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-05. Updated: 2026-11-05  
License: CC BY 4.0 with a link back

CVE-2026-116573 · Severity: medium · CVSS 6.5 · Published 2026-11-05

FreeSWITCH is an open-source telecommunications platform used to handle VoIP calls and messaging. A flaw in the dialog notification feature allows a remote attacker to crash the entire platform and disconnect all active calls by sending a specially crafted SIP message with an excessively long user identifier. Exploitation typically requires valid credentials or specific configuration settings to be disabled.

Technologies: [SignalWire FreeSWITCH](https://junglewise.ai/threats/technologies/freeswitch). Vendors: [SignalWire](https://junglewise.ai/threats/vendors/signalwire).

## Quick answers

**Is CVE-2026-116573 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-116573 being exploited in the wild.

**How severe is CVE-2026-116573?** Medium severity, with a CVSS score of 6.5, published 5 November 2026.

**Which products and versions are affected?** SignalWire FreeSWITCH 1.10.0 to 1.11.1.

**Is there a fix for CVE-2026-116573?** Yes: fixed in 1.11.2. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-116573 attacked?** It is attacked over the network, in a hosted service.

**Am I affected by CVE-2026-116573?** Check whether you run SignalWire FreeSWITCH at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- Fixed in 1.11.2

## Technical details

A stack-based buffer overflow exists in mod_sofia's sofia_dialog_probe_callback() function, where a fixed 512-byte buffer is filled using unbounded strcpy() with user-controlled SIP To-header data. When a peer establishes a dialog with a user part longer than 511 bytes and another peer subscribes to dialog-event notifications, the stored value overflows the stack buffer. The vulnerability requires presence or shared-appearance management to be enabled and typically requires valid profile credentials unless subscription authentication is disabled.

## Affected products

- SignalWire FreeSWITCH 1.10.0 to 1.11.1

## Timeline

- 2026-11-05: disclosed

## References

- [https://github.com/signalwire/freeswitch/commit/49f39c074a5bf81c754619e37ec9e39f2407101f](https://github.com/signalwire/freeswitch/commit/49f39c074a5bf81c754619e37ec9e39f2407101f)
- [https://github.com/signalwire/freeswitch/releases/tag/v1.11.2](https://github.com/signalwire/freeswitch/releases/tag/v1.11.2)

## Related threats

- [FreeSWITCH ICE integrity validation bypass](https://junglewise.ai/threats/cve-2026-116790-freeswitch-is-a-software-defined-telecom-stack-enabling-the)
- [FreeSWITCH DTLS fingerprint validation bypass in server role](https://junglewise.ai/threats/cve-2026-116789-freeswitch-is-a-software-defined-telecom-stack-enabling-the)
- [FreeSWITCH integer underflow in XML decode](https://junglewise.ai/threats/cve-2026-116788-freeswitch-is-an-open-source-software-telecommunications)
- [FreeSWITCH mod_event_socket denial of service via Content-Length](https://junglewise.ai/threats/cve-2026-116787-freeswitch-is-a-software-defined-telecom-stack-enabling-the)
- [FreeSWITCH command injection via SIP REFER URI parameters](https://junglewise.ai/threats/cve-2026-116786-freeswitch-is-a-software-defined-telecom-stack-enabling-the)