CVE-2026-68552
Coturn: uint16_t truncation overflow in STUN message length causes TCP stream framing bypass
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
| NVDNVD · Deferred | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
- EPSS (exploitation in 30 days)
- 0.52% · top 55% of all CVEs (5 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.3.
Weakness
Affected products
References (4)
- https://github.com/coturn/coturn/security/advisories/GHSA-m562-mf7x-q7rr (opens in a new tab)x_refsource_CONFIRM
- https://github.com/coturn/coturn/pull/1964 (opens in a new tab)x_refsource_MISC
- https://github.com/coturn/coturn/commit/ed32e1fb6c843f9cf9a28d91c541dfbf40874f25 (opens in a new tab)x_refsource_MISC
- https://github.com/coturn/coturn/releases/tag/4.15.0 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-68552)Record last updated .