Coturn is a free open source implementation of TURN and STUN Server. Prior to 4.15.0, an on-path attacker can append attributes after MESSAGE-INTEGRITY to an authenticated STUN request on plain UDP or TCP, adjust the STUN header length, and recompute the unkeyed FINGERPRINT while the original HMAC remains valid because it covers only the message prefix. Server-side parsing in src/server/ns_turn_server.c continues past MESSAGE-INTEGRITY through handle_turn_allocate(), handle_turn_create_permission(), handle_turn_refresh(), and handle_turn_command(), allowing trailing LIFETIME, XOR-PEER-ADDRESS, or ORIGIN attributes to override allocation lifetime, inject a permission, or bypass the origin check. TLS and DTLS deployments prevent this in-transit modification. This issue is fixed in version 4.15.0.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-345",
"CWE-924"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/68xxx/CVE-2026-68554.json"
}"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-68554.json"
[
{
"deprecated": false,
"digest": {
"line_hashes": [
"187607345595131467902693838462308306752",
"72002147926325709036944611097215255428",
"25756305666713704789275818757194638155",
"263440164181219378724845800478742993734"
],
"threshold": 0.9
},
"id": "CVE-2026-68554-2c4b5542",
"signature_type": "Line",
"signature_version": "v1",
"source": "https://github.com/coturn/coturn/commit/ab762f334f511ea37ab4b703a47d5d683a5be978",
"target": {
"file": "src/client/ns_turn_msg.h"
}
},
{
"deprecated": false,
"digest": {
"function_hash": "41643669894682188215094192734999739723",
"length": 1390
},
"id": "CVE-2026-68554-68076039",
"signature_type": "Function",
"signature_version": "v1",
"source": "https://github.com/coturn/coturn/commit/ab762f334f511ea37ab4b703a47d5d683a5be978",
"target": {
"file": "tests/test_stun_msg.c",
"function": "main"
}
},
{
"deprecated": false,
"digest": {
"line_hashes": [
"15871114836253548318662383286331414963",
"298880985427035940686424378638557042449",
"295304558891554527111223066887222301419"
],
"threshold": 0.9
},
"id": "CVE-2026-68554-6aeac0a4",
"signature_type": "Line",
"signature_version": "v1",
"source": "https://github.com/coturn/coturn/commit/ab762f334f511ea37ab4b703a47d5d683a5be978",
"target": {
"file": "src/client/ns_turn_msg.c"
}
},
{
"deprecated": false,
"digest": {
"line_hashes": [
"119868789062684038076780377334397840958",
"127944157914558355018717680925014055619",
"207845877431562762415141707443052002303",
"173466160738353120640649015418801402838",
"130264786424818480905268558415513475544",
"160699826502064847153740675057190707354",
"188498266505800062820506194427657309265",
"313195527747018159136669519852929186555",
"129650714188928319433322190275339965204",
"69509710144120563558818407051624818135",
"160699826502064847153740675057190707354",
"188498266505800062820506194427657309265",
"313195527747018159136669519852929186555",
"202661468279049185819036880291725954750",
"128070972249786445507408225435366325745",
"160699826502064847153740675057190707354",
"188498266505800062820506194427657309265",
"313195527747018159136669519852929186555",
"202661468279049185819036880291725954750",
"128070972249786445507408225435366325745",
"160699826502064847153740675057190707354",
"188498266505800062820506194427657309265",
"313195527747018159136669519852929186555",
"202661468279049185819036880291725954750",
"128070972249786445507408225435366325745",
"160699826502064847153740675057190707354",
"188498266505800062820506194427657309265",
"313195527747018159136669519852929186555",
"202661468279049185819036880291725954750",
"128070972249786445507408225435366325745",
"160699826502064847153740675057190707354",
"188498266505800062820506194427657309265",
"313195527747018159136669519852929186555",
"202661468279049185819036880291725954750",
"128070972249786445507408225435366325745",
"160699826502064847153740675057190707354",
"188498266505800062820506194427657309265",
"313195527747018159136669519852929186555",
"256707401688654530629271838531912110626",
"191284267879359825927312182199866908628",
"215620217147277757356951572598498271302",
"188498266505800062820506194427657309265",
"313195527747018159136669519852929186555",
"53597120919103635726294934715965370276",
"97686129899414388758967660024117526569",
"173205682747106853742074059494550555041",
"111783162366610146571522764805534515201",
"202767485279707690909045721526893904220",
"247544072810209847612899370230803679022",
"294626348394847509623572290731359510505",
"120264278195565615155804568365548047310",
"303937136975523773308155065858366886463",
"202767485279707690909045721526893904220",
"118644154901063452926503856084123392954",
"184255186906293936257639342915725686501",
"141814230768592929624385416510113607195",
"303937136975523773308155065858366886463",
"202767485279707690909045721526893904220",
"53597120919103635726294934715965370276",
"84505916145337152588527072005426044791"
],
"threshold": 0.9
},
"id": "CVE-2026-68554-80f0f668",
"signature_type": "Line",
"signature_version": "v1",
"source": "https://github.com/coturn/coturn/commit/ab762f334f511ea37ab4b703a47d5d683a5be978",
"target": {
"file": "src/server/ns_turn_server.c"
}
},
{
"deprecated": false,
"digest": {
"line_hashes": [
"204264647642819134279468588358761980031",
"151486431553365481736026869398605468319",
"145426058790275659148002931451883319750",
"119677661815412017462069349365727237742",
"238603036093953884163760840419892657312",
"161461567659262211115797072116247587856"
],
"threshold": 0.9
},
"id": "CVE-2026-68554-956e0590",
"signature_type": "Line",
"signature_version": "v1",
"source": "https://github.com/coturn/coturn/commit/ab762f334f511ea37ab4b703a47d5d683a5be978",
"target": {
"file": "tests/test_stun_msg.c"
}
},
{
"deprecated": false,
"digest": {
"line_hashes": [
"145491667071940271992096766684929412445",
"331074818928952310801444993394345296731",
"86091485466025133790736394720457652458",
"185297468745095198454760359449943616142"
],
"threshold": 0.9
},
"id": "CVE-2026-68554-9eebd13e",
"signature_type": "Line",
"signature_version": "v1",
"source": "https://github.com/coturn/coturn/commit/ab762f334f511ea37ab4b703a47d5d683a5be978",
"target": {
"file": "src/apps/common/stun_buffer.h"
}
},
{
"deprecated": false,
"digest": {
"line_hashes": [
"233924538414574426215604600836200853978",
"213591367050566838669431551940691013636",
"260830174164741497206814035696001588167",
"323124196554172250270967826065697233890"
],
"threshold": 0.9
},
"id": "CVE-2026-68554-c8274d27",
"signature_type": "Line",
"signature_version": "v1",
"source": "https://github.com/coturn/coturn/commit/ab762f334f511ea37ab4b703a47d5d683a5be978",
"target": {
"file": "src/apps/uclient/startuclient.c"
}
},
{
"deprecated": false,
"digest": {
"line_hashes": [
"11432378877426092216101978059817140434",
"305743017230572670308332177981904421711",
"169701836712138994926500645964312129732",
"82017588760602730439941985218095933532",
"11432378877426092216101978059817140434",
"305743017230572670308332177981904421711",
"334370432304838505799266541293297406917",
"186817433119114874629248419544529833212"
],
"threshold": 0.9
},
"id": "CVE-2026-68554-d2edea0a",
"signature_type": "Line",
"signature_version": "v1",
"source": "https://github.com/coturn/coturn/commit/ab762f334f511ea37ab4b703a47d5d683a5be978",
"target": {
"file": "src/apps/uclient/uclient.c"
}
},
{
"deprecated": false,
"digest": {
"line_hashes": [
"125122199530685286022081423195708142768",
"333903053368523609292492231427845815579",
"58056794171469991762277780672815423501"
],
"threshold": 0.9
},
"id": "CVE-2026-68554-e6626d6d",
"signature_type": "Line",
"signature_version": "v1",
"source": "https://github.com/coturn/coturn/commit/ab762f334f511ea37ab4b703a47d5d683a5be978",
"target": {
"file": "src/apps/common/stun_buffer.c"
}
}
]
"2026-09-11T08:36:44Z"