CVE-2026-40613 (GCVE-0-2026-40613)
Vulnerability from cvelistv5 – Published: 2026-04-21 18:00 – Updated: 2026-04-21 20:36
VLAI
EPSS
VEX
Title
Coturn: Misaligned Memory Access in coturn STUN Attribute Parser (Remote DoS on ARM64)
Summary
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.
Severity
7.5 (High)
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-21 19:54 UTC
CWE
- CWE-704 - Incorrect Type Conversion or Cast
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/coturn/coturn/security/advisor… | x_refsource_CONFIRM |
Impacted products
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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