Description
Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.15.0, an unauthenticated remote client can send a STUN message over TCP or TLS with a body-length field from 65520 through 65532, causing the uint16_t len variable in stun_get_message_len_str() in src/client/ns_turn_msg.c to wrap when STUN_HEADER_LENGTH is added. The framing layer then consumes only 4 through 16 bytes, treats the remaining bytes as another message, desynchronizes the stream parser, and drops the attacking client's connection. Other clients and the server process are not affected. This issue is fixed in version 4.15.0.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| coturn | coturn | < 4.15.0 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | coturn | 4.15.0-1 | — |
| Debian 13 | coturn | No fix yet | — |
| Debian 12 | coturn | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | coturn | No fix yet | — |
| Ubuntu 26.04 LTS | coturn | No fix yet | — |
| Ubuntu 24.04 LTS | coturn | No fix yet | — |
| Ubuntu 22.04 LTS | coturn | No fix yet | — |
| Ubuntu 20.04 LTS | coturn | No fix yet | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | coturn | No fix yet | — |
| Ubuntu 16.04 LTS | coturn | No fix yet | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | coturn | 4.17.2-1.1 | openSUSE-SU-2026:11617-1 |
Advisories 1
- openSUSE-SU-2026:11617-1 coturn-4.17.2-1.1 on GA media SUSE / openSUSE Security Updates · Aug 28, 2026