{"id":"CVE-2026-98997","kind":"vulnerability","aliases":["CVE-2026-98997"],"related":[],"title":"Linux amdgpu driver: doorbell buffer check lets a client wipe shared buffers","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ndrm/amdgpu/userq: only accept doorbell BOs as queue doorbell\n\namdgpu_userq_get_doorbell_index() pins any BO passed as doorbell_handle\ninto the doorbell domain. For a regular BO, TTM moves it with\nttm_bo_move_null() and its contents are lost. Since an importer on the\nsame device gets the exporter's GEM object, a client can do this to a\nbuffer another client shared with it.\n\nReject BOs that were not created in the doorbell domain.\n\nv2: drop the error message, use a local abo variable (Christian)\n\n(cherry picked from commit f7497bbc19db4821c62b9d97b31c9086feb2d917)","summary":"The amdgpu GPU driver in the Linux kernel accepted any buffer object as a user queue doorbell, which pins it into the doorbell memory domain and discards its contents. A client on the same device can use this against a buffer another client shared with it, destroying that data.","severity":"unknown","cvss":null,"epss":0.00206,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["amdgpu","gpu-drivers","linux","runtime"],"not_affected_if":[],"how_to_check":null,"fix":null,"status":"open","published_at":"2026-10-23T13:17:21+00:00","first_seen_at":"2026-10-23T21:57:33+00:00","triaged_at":"2026-10-25T04:56:00+00:00","updated_at":"2026-10-25T12:38:50+00:00","category":"runtime","confidence":0.5,"triage":{"at":"2026-10-25T04:56:00Z","model":"claude-haiku-5-5","output":{"fix":"unknown","reach":"local","title":"Linux amdgpu driver: doorbell buffer check lets a client wipe shared buffers","impact":"low","summary":"The amdgpu GPU driver in the Linux kernel accepted any buffer object as a user queue doorbell, which pins it into the doorbell memory domain and discards its contents. A client on the same device can use this against a buffer another client shared with it, destroying that data.","category":"runtime","nicknames":[],"who_cares":["linux","amdgpu","gpu-drivers"],"confidence":0.5,"needs_auth":"unknown","worst_case":"Shared GPU buffer contents are erased by another client on the device","analyst_note":"Check the NVD entry and the upstream kernel stable commit f7497bbc19db for affected kernel version ranges and whether the fix is in the stable branches.","how_to_check":"unknown","needs_analyst":true,"not_affected_if":[],"who_is_affected":"unknown","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"unknown"},"cost_usd":0.000534,"input_tokens":3467,"output_tokens":375,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-2026':14A,17A '-98997':15A,18A 'abo':169C 'accept':33B,86C 'amdgpu':2A,19B,26B,92C 'anoth':66B,146C 'bo':99C,111C,117C 'bos':88C,152C 'buffer':5A,12A,35B,65B,145C 'check':6A 'cherri':172C 'christian':171C 'client':9A,55B,67B,139C,147C 'commit':175C 'content':53B,122C 'creat':156C 'cve':13A,16A 'data':73B 'destroy':71B 'devic':59B,131C 'discard':51B 'domain':49B,107C,160C 'doorbel':4A,41B,47B,87C,91C,95C,102C,106C,159C 'driver':3A,22B,28B 'drm/amdgpu/userq':84C 'drop':162C 'error':164C 'export':134C 'f7497bbc19db4821c62b9d97b31c9086feb2d917':176C 'follow':79C 'gem':136C 'get':94C,132C 'gpu':21B,27B 'gpu-driv':20B 'handl':103C 'import':127C 'index':96C 'kernel':32B,77C 'let':7A 'linux':1A,23B,31B,76C 'local':168C 'lost':124C 'memori':48B 'messag':165C 'move':113C,118C 'null':119C 'object':36B,137C 'pass':100C 'pick':173C 'pin':43B,97C 'queue':40B,90C 'regular':110C 'reject':151C 'resolv':83C 'runtim':24B 'share':11A,68B,148C 'sinc':125C 'ttm':112C,116C 'use':61B,166C 'user':39B 'userq':93C 'v2':161C 'variabl':170C 'vulner':80C 'wipe':10A","nicknames":[],"mitigations":[],"who_affected":null,"tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-23T13:17:21+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-98997","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-98997","severity":null,"published_at":"2026-10-23T13:17:21+00:00","modified_at":"2026-10-23T13:17:21+00:00","first_seen_at":"2026-10-23T21:57:33+00:00","fetched_at":"2026-10-23T22:29:03+00:00","note":null},{"source":"epss","external_id":"CVE-2026-98997","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-98997","severity":null,"published_at":null,"modified_at":null,"first_seen_at":"2026-10-25T12:38:50+00:00","fetched_at":"2026-10-25T12:38:50+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"}