{"schemaVersion":3,"id":"CVE-2026-68555","aliases":["UBUNTU-CVE-2026-68555","DEBIAN-CVE-2026-68555"],"status":"published","duplicateOf":null,"title":"coturn: Chained mobility resumes allow authenticated remote memory exhaustion","description":"Coturn is a free open source implementation of TURN and STUN Server. In 4.15.0, an authenticated TURN user can repeatedly resume one allocation from fresh UDP 5-tuples without completing a handoff when the server enables --mobility. mobile_begin_transition() in src/server/ns_turn_server.c disarms each new session's allocation timeout and overwrites the allocation's single mobile_pending_resume link, leaving earlier pending sessions unreachable by the cleanup path, while copy_auth_parameters() ignores inc_quota() failure. The attacker can therefore retain unbounded server-side sessions and exhaust process memory even when --user-quota=1 is configured. This issue is fixed in version 4.16.0.","dates":{"published":"2026-08-19T20:43:11.038Z","modified":"2026-08-21T18:14:20.511Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":6.5,"severity":"medium","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":6.5,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"OSV · Ubuntu","score":6.5,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","exploitability":7.2,"impact":6,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"OSV · Debian","score":6.5,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","exploitability":7.2,"impact":6,"computed":true},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":6.5,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.0053,"percentile":0.44003,"severity":"low","asOf":"2026-10-22T00:00:00.000Z","change":{"pp":0.16199999999999998,"baselineDate":"2026-09-22T00:00:00.000Z","baselineScore":0.00368},"history":[{"date":"2026-09-14T00:00:00.000Z","score":0.00368,"percentile":null},{"date":"2026-09-15T00:00:00.000Z","score":0.00368,"percentile":null},{"date":"2026-09-16T00:00:00.000Z","score":0.00368,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.00368,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.00368,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.00368,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.00368,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.00368,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.00368,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.00368,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-21T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-22T00:00:00.000Z","score":0.0053,"percentile":0.44003}],"last30":[{"date":"2026-09-22T00:00:00.000Z","score":0.00368,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.00368,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-21T00:00:00.000Z","score":0.0053,"percentile":null},{"date":"2026-10-22T00:00:00.000Z","score":0.0053,"percentile":0.44003}]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[],"exploitCount":0,"weaknesses":[{"id":"CWE-400","name":"Uncontrolled Resource Consumption","description":"The product does not properly control the allocation and maintenance of a limited resource.","type":"weakness","status":"Draft","abstraction":"Class","likelihoodOfExploit":"High","url":"https://cwe.mitre.org/data/definitions/400.html"}],"affected":[{"vendor":"coturn","product":"coturn","name":"coturn","label":"coturn","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"≥ 4.15.0, < 4.16.0","noFixRecorded":false,"fixedIn":null}],"versionsText":"≥ 4.15.0, < 4.16.0","eol":null,"hubHref":"/vendor/coturn/coturn"},{"vendor":"debian","product":"coturn","name":"coturn","label":"coturn","ecosystem":"Debian","cpePart":null,"purl":"pkg:deb/debian/coturn","purlType":"deb","versions":[{"text":"All versions","noFixRecorded":true,"fixedIn":null},{"text":"< 4.18.0-1","noFixRecorded":false,"fixedIn":null}],"versionsText":"All versions (No fix recorded) | < 4.18.0-1","eol":null,"hubHref":null},{"vendor":"ubuntu","product":"coturn","name":"coturn","label":"coturn","ecosystem":"Ubuntu","cpePart":null,"purl":"pkg:deb/ubuntu/coturn","purlType":"deb","versions":[{"text":"All versions","noFixRecorded":true,"fixedIn":null}],"versionsText":"All versions (No fix recorded)","eol":null,"hubHref":null}],"affectedCount":3,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://github.com/coturn/coturn/security/advisories/GHSA-hpq3-g7x4-h7xx","label":"github.com/coturn/coturn/security/advisories/GHSA-hpq3-g7x4-h7xx","hostname":"github.com","tags":["X Refsource CONFIRM","REPORT"]},{"url":"https://github.com/coturn/coturn/commit/a97f1924bb435bec49d6d91ae01fa2487c2e1bf7","label":"github.com/coturn/coturn/commit/a97f1924bb435bec49d6d91ae01fa2487c2e1bf7","hostname":"github.com","tags":["X Refsource MISC","REPORT"]},{"url":"https://github.com/coturn/coturn/releases/tag/4.16.0","label":"github.com/coturn/coturn/releases/tag/4.16.0","hostname":"github.com","tags":["X Refsource MISC","REPORT"]},{"url":"https://ubuntu.com/security/CVE-2026-68555","label":"ubuntu.com/security/CVE-2026-68555","hostname":"ubuntu.com","tags":["REPORT"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-68555","label":"www.cve.org/CVERecord?id=CVE-2026-68555","hostname":"www.cve.org","tags":["REPORT"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-68555","label":"security-tracker.debian.org/tracker/CVE-2026-68555","hostname":"security-tracker.debian.org","tags":["Advisory"]}],"lineage":{"upstream":[],"downstream":["OPENSUSE-SU-2026:11617-1"],"duplicates":[],"related":["OPENSUSE-SU-2026:11617-1"]},"timeline":[{"kind":"published","date":"2026-08-19T20:43:11.038Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2026-08-21T18:14:20.511Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":26,"level":"medium","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-22T19:43:29.647Z","stale":false,"partial":false}}