CVE-2026-40613

published 2026-04-21

CVE-2026-40613: Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.10.0, the STUN/TURN attribute parsing functions in coturn perform unsafe…

Priority P3 46 high 7.5 CVSS 3.1

AV N AC L PR N UI N S U C N I N A H

Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.10.0, the STUN/TURN attribute parsing functions in coturn perform unsafe pointer casts from uint8_t * to uint16_t * without alignment checks. When processing a crafted STUN message with odd-aligned attribute boundaries, this results in misaligned memory reads at ns_turn_msg.c. On ARM64 architectures (AArch64) with strict alignment enforcement, this causes a SIGBUS signal that immediately kills the turnserver process. An unauthenticated remote attacker can crash any ARM64 coturn deployment by sending a single crafted UDP packet. This vulnerability is fixed in 4.10.0.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
coturn	coturn	< 4.10.0	4.10.0
coturn_project	coturn	< 4.10.0	4.10.0

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