# SIPSorcery TurnServer denial of service via malformed UDP datagram

Source: https://junglewise.ai/threats/sipsorcery-turnserver-denial-of-service-via-malformed-udp-datagram-96530cb3  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-12. Updated: 2026-08-12  
License: CC BY 4.0 with a link back

Severity: high · CVSS 7.5 · Published 2026-08-12

A vulnerability in the SIPSorcery library's TURN server component allows a remote attacker to crash the communication service by sending a single specially crafted network packet. This component is responsible for relaying media traffic between users; if crashed, all active and new connections for all users will fail until the server is manually restarted. This results in a complete denial of service for the affected communication features.

Technologies: [SIPSorcery (NuGet)](https://junglewise.ai/threats/technologies/sipsorcery). Vendors: [NuGet](https://junglewise.ai/threats/vendors/nuget).

## Quick answers

**Is This vulnerability exploited in the wild?** No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

**How severe is This vulnerability?** High severity, with a CVSS score of 7.5, published 12 August 2026.

**Which products and versions are affected?** SIPSorcery (NuGet) >= 10.0.5, <= 10.0.13.

**Is there a fix for This vulnerability?** A patch was published on 2026-08-12: Fixed in version 10.0.14 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is This vulnerability attacked?** It is attacked over the network, in a software library.

**Am I affected?** Check whether you run SIPSorcery (NuGet) 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.

## Technical details

The TurnServer.ReceiveUdpAsync method in SIPSorcery (versions 10.0.5 through 10.0.13) contains a logic error where the primary packet processing logic (HandleUdpDatagram) resides outside of the try-catch block within its receive loop. An unauthenticated attacker can send a UDP datagram with a specific first byte (0x80–0xFF) that triggers an ApplicationException during STUN header parsing. Because the exception is caught outside the loop, the receive thread terminates without a supervisor to restart it, effectively disabling the TURN UDP relay for all clients. The issue is fixed in version 10.0.14 by ensuring exceptions during packet processing do not terminate the listener loop.

## Affected products

- SIPSorcery SIPSorcery 10.0.5 - 10.0.13

## Timeline

- 2026-08-12: advisory: GHSA-pfvm-w89x-94jw published
- 2026-08-12: patched: Fixed in version 10.0.14

## References

- [https://api.github.com/users/manus-use](https://api.github.com/users/manus-use)
- [https://github.com/manus-use](https://github.com/manus-use)
- [https://api.github.com/users/manus-use/gists%7B/gist_id%7D](https://api.github.com/users/manus-use/gists%7B/gist_id%7D)
- [https://api.github.com/users/manus-use/repos](https://api.github.com/users/manus-use/repos)
- [https://avatars.githubusercontent.com/u/213290975?v=4](https://avatars.githubusercontent.com/u/213290975?v=4)
- [https://api.github.com/users/manus-use/events%7B/privacy%7D](https://api.github.com/users/manus-use/events%7B/privacy%7D)

## Related threats

- [SIPSorcery remote denial of service via malformed UDP packet](https://junglewise.ai/threats/cve-2026-54632-sipsorcery-remote-denial-of-service-via-malformed-udp-packet)
- [SIPSorcery out-of-bounds read in SCTP SACK chunk parsing](https://junglewise.ai/threats/sipsorcery-out-of-bounds-read-in-sctp-sack-chunk-parsing-365efd66)