coturn — security advisory
Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.15.0, a server using --mobility authenticates a resumed REFRESH request with the resuming user's credentials but does not verify that identity against the original allocation owner, allowing an authenticated attacker who obtains a victim MOBILITY-TICKET to receive and inject relayed traffic and consume the victim's quota. In the handle_turn_refresh resume branch, the victim allocation (orig_ss) is located solely by the attacker-controlled mobile id, and credentials are only adopted (via copy_auth_parameters) when the resuming session is unauthenticated. Because the attacker's session already has hmackey_set set to 1 from its own prior authentication (which is never reset for long-term-credential sessions), the credential copy is skipped and check_stun_auth validates the REFRESH against the attacker's own identity rather than the allocation owner's. This issue is fixed in version 4.15.0.
- 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
- 4.15.0-1
- CVEs
- CVE-2026-65981
- 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 4.15.0, a server using --mobility authenticates a resumed REFRESH request with the resuming user's credentials but does not verify that identity against the original allocation owner, allowing an authenticated attacker who obtains a victim MOBILITY-TICKET to receive and inject relayed traffic and consume the victim's quota. In the handle_turn_refresh resume branch, the victim allocation (orig_ss) is located solely by the attacker-controlled mobile id, and credentials are only adopted (via copy_auth_parameters) when the resuming session is unauthenticated. Because the attacker's session already has hmackey_set set to 1 from its own prior authentication (which is never reset for long-term-credential sessions), the credential copy is skipped and check_stun_auth validates the REFRESH against the attacker's own identity rather than the allocation owner's. This issue is fixed in version 4.15.0.
osv:DEBIAN-CVE-2026-65981
coturn
Fixed versions: Not specified
coturn
Fixed versions: Not specified
coturn
Fixed versions: 4.15.0-1
Complete source record
{
"id": "fe0551ef7cfb2f87e5a11594341b43ac3f019021e797826af9f0ddb7e8fe58d6",
"url": "https://osv.dev/vulnerability/DEBIAN-CVE-2026-65981",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "DEBIAN-CVE-2026-65981",
"summary": "Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.15.0, a server using --mobility authenticates a resumed REFRESH request with the resuming user's credentials but does not verify that identity against the original allocation owner, allowing an authenticated attacker who obtains a victim MOBILITY-TICKET to receive and inject relayed traffic and consume the victim's quota. In the handle_turn_refresh resume branch, the victim allocation (orig_ss) is located solely by the attacker-controlled mobile id, and credentials are only adopted (via copy_auth_parameters) when the resuming session is unauthenticated. Because the attacker's session already has hmackey_set set to 1 from its own prior authentication (which is never reset for long-term-credential sessions), the credential copy is skipped and check_stun_auth validates the REFRESH against the attacker's own identity rather than the allocation owner's. This issue is fixed in version 4.15.0.",
"evidence": "osv:DEBIAN-CVE-2026-65981",
"products": [
{
"name": {
"value": "coturn",
"evidence": "/affected/0/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "4.12.0-1",
"evidence": "/affected/0/versions"
},
{
"value": "4.14.0-1",
"evidence": "/affected/0/versions"
},
{
"value": "4.15.0-1",
"evidence": "/affected/0/versions"
},
{
"value": "4.18.0-1",
"evidence": "/affected/0/versions"
},
{
"value": "4.6.1-1",
"evidence": "/affected/0/versions"
},
{
"value": "4.6.1-2",
"evidence": "/affected/0/versions"
}
]
},
{
"name": {
"value": "coturn",
"evidence": "/affected/1/package/name"
},
"prerequisites": [],
"fixed_versions": [],
"affected_versions": [
{
"value": "4.12.0-1",
"evidence": "/affected/1/versions"
},
{
"value": "4.14.0-1",
"evidence": "/affected/1/versions"
},
{
"value": "4.15.0-1",
"evidence": "/affected/1/versions"
},
{
"value": "4.18.0-1",
"evidence": "/affected/1/versions"
},
{
"value": "4.6.1-2",
"evidence": "/affected/1/versions"
}
]
},
{
"name": {
"value": "coturn",
"evidence": "/affected/2/package/name"
},
"prerequisites": [],
"fixed_versions": [
{
"value": "4.15.0-1",
"evidence": "/affected/2/ranges"
}
],
"affected_versions": [
{
"value": "4.12.0-1",
"evidence": "/affected/2/versions"
},
{
"value": "4.14.0-1",
"evidence": "/affected/2/versions"
},
{
"value": "4.6.1-2",
"evidence": "/affected/2/versions"
}
]
}
],
"severity": "high",
"structured": {
"id": "DEBIAN-CVE-2026-65981",
"aliases": [
"DEBIAN-CVE-2026-65981"
],
"metrics": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:L"
}
],
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "coturn",
"purl": "pkg:deb/debian/coturn?arch=source&distro=bookworm",
"ecosystem": "Debian:12"
},
"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"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-65981.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
}
]
}
],
"package": {
"name": "coturn",
"purl": "pkg:deb/debian/coturn?arch=source&distro=trixie",
"ecosystem": "Debian:13"
},
"versions": [
"4.12.0-1",
"4.14.0-1",
"4.15.0-1",
"4.18.0-1",
"4.6.1-2"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-65981.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "4.15.0-1"
}
]
}
],
"package": {
"name": "coturn",
"purl": "pkg:deb/debian/coturn?arch=source&distro=forky",
"ecosystem": "Debian:14"
},
"versions": [
"4.12.0-1",
"4.14.0-1",
"4.6.1-2"
],
"database_specific": {
"source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-65981.json"
},
"ecosystem_specific": {
"urgency": "not yet assigned"
}
}
],
"modified": "2026-10-10T16:00:07.484055880Z",
"provider": "osv",
"upstream": [
"CVE-2026-65981"
],
"references": [
"https://security-tracker.debian.org/tracker/CVE-2026-65981"
]
},
"related_cves": [
{
"value": "CVE-2026-65981",
"evidence": "/upstream"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 250474,
"published_at": "2026-07-31T21:17:31.857+00:00"
}