CVE-2026-68554

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/coturn/coturn/commit/ab762f334f511ea37ab4b703a47d5d683a5be978
https://github.com/coturn/coturn/releases/tag/4.15.0
https://github.com/coturn/coturn/security/advisories/GHSA-5538-7cxj-5jcc
https://github.com/coturn/coturn/security/advisories/GHSA-5538-7cxj-5jcc

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-19 21:17

Updated : 2026-09-09 21:20

NVD link : CVE-2026-68554

Mitre link : CVE-2026-68554

CVE.ORG link : CVE-2026-68554

JSON object : View

Products Affected

No product.

CWE

CWE-345

Insufficient Verification of Data Authenticity

CWE-924

Improper Enforcement of Message Integrity During Transmission in a Communication Channel

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