CVE-2026-68554

Coturn: STUN attributes after MESSAGE-INTEGRITY are processed, letting on-path attackers modify authenticated TURN requests

Published: Aug 19, 2026Updated: Sep 9, 2026 Sources: CVE List NVDCWE-345

N/ACVSS

NVD MITRE

Description

Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.15.0, an on-path attacker can append attributes after MESSAGE-INTEGRITY to an authenticated STUN request on plain UDP or TCP, adjust the STUN header length, and recompute the unkeyed FINGERPRINT while the original HMAC remains valid because it covers only the message prefix. Server-side parsing in src/server/ns_turn_server.c continues past MESSAGE-INTEGRITY through handle_turn_allocate(), handle_turn_create_permission(), handle_turn_refresh(), and handle_turn_command(), allowing trailing LIFETIME, XOR-PEER-ADDRESS, or ORIGIN attributes to override allocation lifetime, inject a permission, or bypass the origin check. TLS and DTLS deployments prevent this in-transit modification. This issue is fixed in version 4.15.0.

No summary for this CVE yet.

Weaknesses

CWE-345 CWE-924

Affected Products

coturn

oss-project

coturnOn-prem

Networking Infrastructure / load-balancer-proxy

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

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References

https://github.com/coturn/coturn/security/advisories/GHSA-5538-7cxj-5jcc

github.com

https://github.com/coturn/coturn/commit/ab762f334f511ea37ab4b703a47d5d683a5be978

github.com

https://github.com/coturn/coturn/releases/tag/4.15.0

github.com

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