{"id":"CVE-2026-98689","kind":"vulnerability","aliases":["CVE-2026-98689"],"related":[],"title":"Linux kernel: Thunderbolt DP tunnel accessed after teardown, causing use-after-free","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nthunderbolt: Don't access a DP tunnel after its DPRX read was canceled\n\ntb_dp_dprx_work() checks ->dprx_canceled before it takes tb->lock so it\nmisses a tb_dp_dprx_stop() that could not cancel the already running\nwork. It then polls the DPRX capabilities and runs the callback for a\ntunnel that has already been torn down while the domain is suspending or\ngoing away.\n\nThis can be hit by cancelling the DPRX read from outside the ordered\ntb->wq: During suspend tb_disconnect_and_release_dp() does just this and\nwith a later patch tb_stop() will do it as well. The latter in combination\nwith the Apple NHI where the DPRX read never completed is how I hit\nthis.\n\nCheck the flag with tb->lock held instead and check it again in\ntb_dp_tunnel_active() because the callback runs after the lock has been\ndropped again.\n\nAlso clear the flag in tb_dp_dprx_start() so that it only ever describes\nthe work that is currently in flight.","summary":"A race in the Linux kernel Thunderbolt driver lets a DisplayPort tunnel be accessed after its DPRX read was cancelled during suspend or shutdown. The sources do not state the exact effect beyond this access to a torn-down tunnel.","severity":"unknown","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["laptops","linux-kernel","runtime","thunderbolt"],"not_affected_if":["no-thunderbolt-hardware"],"how_to_check":"- unknown","fix":"- unknown","status":"open","published_at":"2026-10-18T16:17:22+00:00","first_seen_at":"2026-10-23T21:57:16+00:00","triaged_at":"2026-10-25T05:19:05+00:00","updated_at":"2026-10-25T05:19:05+00:00","category":"runtime","confidence":0.3,"triage":{"at":"2026-10-25T05:19:05Z","model":"claude-haiku-5-5","output":{"fix":"- unknown","reach":"local","title":"Linux kernel: Thunderbolt DP tunnel accessed after teardown, causing use-after-free","impact":"medium","summary":"A race in the Linux kernel Thunderbolt driver lets a DisplayPort tunnel be accessed after its DPRX read was cancelled during suspend or shutdown. The sources do not state the exact effect beyond this access to a torn-down tunnel.","category":"runtime","nicknames":[],"who_cares":["linux-kernel","thunderbolt","laptops"],"confidence":0.3,"needs_auth":"unknown","worst_case":"unknown; kernel-level access to a torn-down tunnel","analyst_note":"Find the upstream kernel commit and fixed stable versions for CVE-2026-98689 and check whether the flaw has a known security impact beyond the race.","how_to_check":"- unknown","needs_analyst":true,"not_affected_if":["no-thunderbolt-hardware"],"who_is_affected":"Systems running a Linux kernel with the Thunderbolt driver and a DisplayPort tunnel over Thunderbolt, where the DPRX read never completes during suspend or teardown. The sources do not say which kernel versions are fixed or which hardware is most exposed. unknown","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"unknown"},"cost_usd":0.000599,"input_tokens":3574,"output_tokens":483,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-2026':15A,18A '-98689':16A,19A 'access':6A,39B,60B,80C 'activ':217C 'alreadi':115C,133C 'also':229C 'appl':188C 'away':144C 'beyond':58B 'callback':127C,220C 'cancel':45B,89C,96C,113C,150C 'capabl':123C 'caus':9A 'check':94C,201C,210C 'clear':230C 'combin':185C 'complet':195C 'could':111C 'current':248C 'cve':14A,17A 'describ':243C 'disconnect':163C 'displayport':36B 'domain':139C 'dp':4A,82C,91C,107C,166C,215C,235C 'dprx':42B,86C,92C,95C,108C,122C,152C,192C,236C 'driver':33B 'drop':227C 'effect':57B 'ever':242C 'exact':56B 'flag':203C,232C 'flight':250C 'follow':72C 'free':13A 'go':143C 'held':207C 'hit':148C,199C 'instead':208C 'kernel':2A,23B,31B,70C 'laptop':20B 'later':173C 'latter':183C 'let':34B 'linux':1A,22B,30B,69C 'linux-kernel':21B 'lock':101C,206C,224C 'miss':104C 'never':194C 'nhi':189C 'order':157C 'outsid':155C 'patch':174C 'poll':120C 'race':27B 'read':43B,87C,153C,193C 'releas':165C 'resolv':76C 'run':116C,125C,221C 'runtim':24B 'shutdown':49B 'sourc':51B 'start':237C 'state':54B 'stop':109C,176C 'suspend':47B,141C,161C 'take':99C 'tb':90C,100C,106C,158C,162C,175C,205C,214C,234C 'teardown':8A 'thunderbolt':3A,25B,32B,77C 'torn':64B,135C 'torn-down':63B 'tunnel':5A,37B,66B,83C,130C,216C 'use':11A 'use-after-fre':10A 'vulner':73C 'well':181C 'work':93C,117C,245C 'wq':159C","nicknames":[],"mitigations":[],"who_affected":"Systems running a Linux kernel with the Thunderbolt driver and a DisplayPort tunnel over Thunderbolt, where the DPRX read never completes during suspend or teardown. The sources do not say which kernel versions are fixed or which hardware is most exposed. unknown","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-18T16:17:22+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-98689","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98689","severity":null,"published_at":"2026-10-18T16:17:22+00:00","modified_at":"2026-10-19T10:19:33+00:00","first_seen_at":"2026-10-23T21:57:16+00:00","fetched_at":"2026-10-23T22:28:56+00:00","note":null}],"documents":[],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}