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 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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/coturn/coturn/security/advisories/GHSA-j662-9wcj-mf36	Exploit Vendor Advisory
https://github.com/coturn/coturn/security/advisories/GHSA-j662-9wcj-mf36	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:coturn_project:coturn:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-04-21 19:16

Updated : 2026-06-17 10:45

NVD link : CVE-2026-40613

Mitre link : CVE-2026-40613

CVE.ORG link : CVE-2026-40613

JSON object : View

Products Affected

coturn_project

coturn

CWE

CWE-704

Incorrect Type Conversion or Cast

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