{"id":"CVE-2026-65981","state":"PUBLISHED","title":"Coturn: MOBILITY-TICKET session-resume authorization bypass allows cross-user TURN allocation takeover","description":"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.","publishedAt":"2026-07-31T21:00:02.893Z","updatedAt":"2026-08-05T13:44:34.433Z","severity":{"score":7.1,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:L","source":"GitHub_M"},"assigner":"GitHub_M","products":["coturn coturn"],"affected":[{"vendor":"coturn","product":"coturn","versions":[{"version":"< 4.15.0","status":"affected"}]}],"references":["https://github.com/coturn/coturn/security/advisories/GHSA-69wx-x7x6-pjj8","https://github.com/coturn/coturn/commit/37df0513168f830a7c9ce0a411db0300fa182f05"],"weaknesses":["CWE-639"],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/65xxx/CVE-2026-65981.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-65981","state":"PUBLISHED","datePublished":"2026-07-31T21:00:02.893Z","dateUpdated":"2026-08-05T13:44:34.433Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-07-23T18:54:15.832Z"},"containers":{"cna":{"title":"Coturn: MOBILITY-TICKET session-resume authorization bypass allows cross-user TURN allocation takeover","descriptions":[{"lang":"en","value":"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."}],"affected":[{"vendor":"coturn","product":"coturn","versions":[{"version":"< 4.15.0","status":"affected"}]}],"references":[{"url":"https://github.com/coturn/coturn/security/advisories/GHSA-69wx-x7x6-pjj8","name":"https://github.com/coturn/coturn/security/advisories/GHSA-69wx-x7x6-pjj8","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/coturn/coturn/commit/37df0513168f830a7c9ce0a411db0300fa182f05","name":"https://github.com/coturn/coturn/commit/37df0513168f830a7c9ce0a411db0300fa182f05","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"LOW","baseScore":7.1,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:L","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-639","lang":"en","description":"CWE-639: Authorization Bypass Through User-Controlled Key","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-07-31T21:00:02.893Z"},"source":{"advisory":"GHSA-69wx-x7x6-pjj8","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/coturn/coturn/security/advisories/GHSA-69wx-x7x6-pjj8","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-08-04T03:56:21.281110Z","id":"CVE-2026-65981","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-05T13:44:34.433Z"}}]}}}