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TI-2026-29348 Aliases CVE-2026-40613

Coturn: Misaligned Memory Access in coturn STUN Attribute Parser (Remote DoS on ARM64)

Priority HIGH 72CWE-704Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-704 and the CVSS impact.

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.01123 66th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed coturn (coturn): 4.10.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
coturncoturnbefore 4.10.04.10.0Patch availableCNA
  • coturn Vendorcoturn Affected before 4.10.0 Fixed in 4.10.0 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:coturn_project:coturn:*:*:*:*:*:*:*:*before 4.10.0Vulnerablecoturn
  • cpe:2.3:a:coturn_project:coturn:*:*:*:*:*:*:*:* Versions before 4.10.0 Vulnerable ·coturn

Remediation

  • Fix · CNA coturn (coturn) Fixed in 4.10.0

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-40613

References

Exploit 1

  • TI-2026-32037 Coturn: Stack buffer overflow in decode_oauth_token_gcm() CVSS 3.1CRITICAL 9.8
  • TI-2026-22006 Coturn: IPv4-mapped IPv6 (::ffff:0:0/96) bypasses denied-peer-ip ACL CVSS 3.1HIGH 7.2
  • TI-2026-38529 Coturn: SQL Injection in HTTPS Admin Panel Delete Operations CVSS 3.1HIGH 7.2
  • TI-2026-38531 Coturn: IPv4-mapped 127.0.0.1 bypasses default loopback peer protection CVSS 3.1HIGH 7.4
  • TI-2026-38530 Coturn: Arbitrary File Write via CLI psd Command CVSS 3.1MEDIUM 6.0
  • TI-2020-04928 Out-of-bounds read in CoTURN CVSS 3.1CRITICAL 9.8
See all 13 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences