CVE-2026-65981

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.

Database specific

{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-639"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/65xxx/CVE-2026-65981.json"
}

References

Affected packages

Git / github.com/coturn/coturn

Affected ranges

Type

GIT

Repo

https://github.com/coturn/coturn

Events

Introduced

Fixed

37df0513168f830a7c9ce0a411db0300fa182f05

Database specific

Show details

{
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "4.15.0"
        }
    ],
    "source": [
        "AFFECTED_FIELD",
        "REFERENCES"
    ]
}

Affected versions

4.*

4.10.0

4.11.0

4.12.0

4.13.0

4.13.1

4.14.0

4.4.5.3

4.4.5.4

4.5.0.1

4.5.0.2

4.5.0.3

4.5.0.4

4.5.0.5

4.5.0.6

4.5.0.7

4.5.1.0

4.5.1.1

4.5.1.2

4.5.1.3

4.5.2

4.6.0

4.6.2

4.6.3

4.7.0

4.8.0

4.9.0

docker/4.*

docker/4.10.0-r0

docker/4.10.0-r1

docker/4.11.0-r0

docker/4.12.0-r0

docker/4.13.0-r0

docker/4.13.1-r0

docker/4.14.0-r0

docker/4.5.2-r0

docker/4.5.2-r10

docker/4.5.2-r11

docker/4.5.2-r12

docker/4.5.2-r13

docker/4.5.2-r14

docker/4.5.2-r6

docker/4.5.2-r7

docker/4.5.2-r8

docker/4.5.2-r9

docker/4.6.0-r0

docker/4.6.0-r1

docker/4.6.1-r0

docker/4.6.1-r1

docker/4.6.1-r2

docker/4.6.1-r3

docker/4.6.2-r0

docker/4.6.2-r1

docker/4.6.2-r10

docker/4.6.2-r11

docker/4.6.2-r12

docker/4.6.2-r13

docker/4.6.2-r2

docker/4.6.2-r3

docker/4.6.2-r4

docker/4.6.2-r5

docker/4.6.2-r6

docker/4.6.2-r7

docker/4.6.2-r8

docker/4.6.2-r9

docker/4.6.3-r0

docker/4.6.3-r1

docker/4.6.3-r2

docker/4.6.3-r3

docker/4.7.0-r0

docker/4.7.0-r1

docker/4.7.0-r2

docker/4.7.0-r3

docker/4.7.0-r4

docker/4.8.0-r0

docker/4.8.0-r1

docker/4.9.0-r0

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-65981.json"

vanir_signatures

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    {
        "deprecated": false,
        "digest": {
            "function_hash": "197916663795514868159840160029149056090",
            "length": 8428
        },
        "id": "CVE-2026-65981-ae564408",
        "signature_type": "Function",
        "signature_version": "v1",
        "source": "https://github.com/coturn/coturn/commit/37df0513168f830a7c9ce0a411db0300fa182f05",
        "target": {
            "file": "src/server/ns_turn_server.c",
            "function": "handle_turn_refresh"
        }
    },
    {
        "deprecated": false,
        "digest": {
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            ],
            "threshold": 0.9
        },
        "id": "CVE-2026-65981-b100d531",
        "signature_type": "Line",
        "signature_version": "v1",
        "source": "https://github.com/coturn/coturn/commit/37df0513168f830a7c9ce0a411db0300fa182f05",
        "target": {
            "file": "src/server/ns_turn_server.c"
        }
    }
]

vanir_signatures_modified

"2026-08-12T16:09:58Z"