{"id":"CVE-2026-98750","kind":"vulnerability","aliases":["CVE-2026-98750"],"related":[],"title":"Linux kernel: TTY saved termios race can cause use-after-free","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntty: fix saved termios reset race\n\nResetting saved termios state on device registration is needed where a\nminor number can be reused for an entirely different device and where\nthe old settings may prevent the port from even being opened (e.g. when\nCLOCAL is not set).\n\nNot all TTY drivers guarantee that the minor number is no longer in use\nwhen registering devices however, something which can lead to a\nuse-after-free when closing a TTY (and saving its termios) races with\nre-registration.\n\nAdd a new TTY_DRIVER_RESET_SAVED_TERMIOS flag to request that any saved\ntermios state is reset on registration and only set it for drivers that\nmake sure that the minor number is no longer in use.","summary":"A race between closing a TTY and re-registering a device that reuses its minor number can cause a use-after-free in the Linux kernel. The sources describe the flaw but do not state what an attacker gains beyond memory corruption.","severity":"unknown","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["infrastructure","linux-kernel","linux-servers","self-hosted"],"not_affected_if":["default-config"],"how_to_check":"- `uname -r` to see the running kernel version\n- unknown whether the sources list affected kernel versions","fix":"- Update the Linux kernel to a release that includes the upstream fix for the TTY saved termios reset race\n- unknown exact fixed version from the sources","status":"open","published_at":"2026-10-18T16:17:28+00:00","first_seen_at":"2026-10-23T21:57:16+00:00","triaged_at":"2026-10-25T05:16:57+00:00","updated_at":"2026-10-25T05:16:57+00:00","category":"infrastructure","confidence":0.4,"triage":{"at":"2026-10-25T05:16:57Z","model":"claude-haiku-5-5","output":{"fix":"- Update the Linux kernel to a release that includes the upstream fix for the TTY saved termios reset race\n- unknown exact fixed version from the sources","reach":"local","title":"Linux kernel: TTY saved termios race can cause use-after-free","impact":"medium","summary":"A race between closing a TTY and re-registering a device that reuses its minor number can cause a use-after-free in the Linux kernel. The sources describe the flaw but do not state what an attacker gains beyond memory corruption.","category":"infrastructure","nicknames":[],"who_cares":["linux-kernel","self-hosted","linux-servers"],"confidence":0.4,"needs_auth":"unknown","worst_case":"unknown; sources describe a use-after-free in kernel memory","analyst_note":"Check the kernel.org stable commit for the fixed version and which TTY drivers are affected; the NVD entry gives no CVSS score.","how_to_check":"- `uname -r` to see the running kernel version\n- unknown whether the sources list affected kernel versions","needs_analyst":true,"not_affected_if":["default-config"],"who_is_affected":"Systems running a Linux kernel with TTY drivers that reuse minor numbers on device registration are the ones the description points at. The sources do not say which drivers or configurations trigger the race, so unknown whether a given server is exposed.","user_interaction":"unknown","needs_special_setup":"unknown","severity_if_unknown":"unknown"},"cost_usd":0.000599,"input_tokens":3457,"output_tokens":506,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-2026':14A,17A '-98750':15A,18A 'add':170C 'attack':68B 'beyond':70B 'caus':8A,47B 'clocal':125C 'close':32B,158C 'corrupt':72B 'cve':13A,16A 'describ':59B 'devic':40B,94C,109C,145C 'differ':108C 'driver':132C,174C,195C 'e.g':123C 'entir':107C 'even':120C 'fix':84C 'flag':178C 'flaw':61B 'follow':78C 'free':12A,52B,156C 'gain':69B 'guarante':133C 'host':28B 'howev':146C 'infrastructur':19B 'kernel':2A,22B,56B,76C 'lead':150C 'linux':1A,21B,24B,55B,75C 'linux-kernel':20B 'linux-serv':23B 'longer':140C,205C 'make':197C 'may':115C 'memori':71B 'minor':44B,100C,136C,201C 'need':97C 'new':172C 'number':45B,101C,137C,202C 'old':113C 'open':122C 'port':118C 'prevent':116C 'race':6A,30B,88C,165C 're':37B,168C 're-regist':36B 're-registr':167C 'regist':38B,144C 'registr':95C,169C,189C 'request':180C 'reset':87C,89C,175C,187C 'resolv':82C 'reus':42B,104C 'save':4A,85C,90C,162C,176C,183C 'self':27B 'self-host':26B 'server':25B 'set':114C,128C,192C 'someth':147C 'sourc':58B 'state':65B,92C,185C 'sure':198C 'termio':5A,86C,91C,164C,177C,184C 'tti':3A,34B,83C,131C,160C,173C 'use':10A,50B,142C,154C,207C 'use-after-fre':9A,49B,153C 'vulner':79C","nicknames":[],"mitigations":[],"who_affected":"Systems running a Linux kernel with TTY drivers that reuse minor numbers on device registration are the ones the description points at. The sources do not say which drivers or configurations trigger the race, so unknown whether a given server is exposed.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-18T16:17:28+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-98750","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98750","severity":null,"published_at":"2026-10-18T16:17:28+00:00","modified_at":"2026-10-21T13:21:43+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"}