coturn — security advisory
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.
- Products
- coturn
- Affected versions
- 4.12.0-1, 4.14.0-1, 4.15.0-1, 4.18.0-1, 4.6.1-1, 4.6.1-2
- Fixed versions
- 4.12.0-1
- CVEs
- CVE-2026-40613
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 29 Oct 2026, 13:52 UTC · Revision 1
Source evidence
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.
osv:DEBIAN-CVE-2026-40613
coturn
Fixed versions: Not specified
coturn
Fixed versions: Not specified
coturn
Fixed versions: 4.12.0-1
Complete source record
{
"id": "bebf42ff75dd9ab11306aaa1c81652db7c55eef4b1c0f4f7b0d6da8f1d6cb75d",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-40613",
"method": "structured",
"payload": {
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"title": "DEBIAN-CVE-2026-40613",
"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.",
"evidence": "osv:DEBIAN-CVE-2026-40613",
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{
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{
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{
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"package": {
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"ecosystem": "Debian:13"
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"versions": [
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"database_specific": {
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"ecosystem_specific": {
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],
"modified": "2026-10-10T16:00:06.415063355Z",
"provider": "osv",
"upstream": [
"CVE-2026-40613"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2026-40613"
]
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"related_cves": [
{
"value": "CVE-2026-40613",
"evidence": "/upstream"
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"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 250467,
"published_at": "2026-04-21T19:16:17.743+00:00"
}