{"id":"CVE-2026-122166","kind":"vulnerability","aliases":["CVE-2026-122166"],"related":[],"title":"Windows Remote Desktop Services: stack overflow lets a local user gain admin rights","description":"Stack-based buffer overflow in Windows Remote Desktop Services allows an authorized attacker to elevate privileges locally.","summary":"A stack-based buffer overflow in Windows Remote Desktop Services lets an attacker who already has an authorized account on the machine raise their privileges. The sources describe this as a local privilege escalation with a CVSS score of 7.8.","severity":"high","cvss":7.8,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["infrastructure","remote-desktop-services","windows"],"not_affected_if":["remote-desktop-services-disabled"],"how_to_check":"- Check the Windows build and patch level with `winver` or `Get-ComputerInfo` and compare it against Microsoft's security update for this CVE\n- Confirm whether Remote Desktop Services is enabled on the host (`Get-Service TermService`)","fix":null,"status":"open","published_at":"2026-11-10T19:20:33+00:00","first_seen_at":"2026-11-10T19:25:10+00:00","triaged_at":"2026-11-10T19:38:58+00:00","updated_at":"2026-11-10T19:38:58+00:00","category":"infrastructure","confidence":0.6,"triage":{"at":"2026-11-10T19:38:58Z","model":"claude-haiku-5-5","output":{"fix":"unknown","reach":"local","title":"Windows Remote Desktop Services: stack overflow lets a local user gain admin rights","impact":"high","summary":"A stack-based buffer overflow in Windows Remote Desktop Services lets an attacker who already has an authorized account on the machine raise their privileges. The sources describe this as a local privilege escalation with a CVSS score of 7.8.","audience":"businesses","category":"infrastructure","nicknames":[],"who_cares":["windows","remote-desktop-services"],"confidence":0.6,"fix_status":"unknown","needs_auth":"yes","worst_case":"attacker gains SYSTEM privileges on the affected Windows machine","analyst_note":"Find the Microsoft security update guide entry for CVE-2026-122166 to confirm affected Windows builds and the patch.","how_to_check":"- Check the Windows build and patch level with `winver` or `Get-ComputerInfo` and compare it against Microsoft's security update for this CVE\n- Confirm whether Remote Desktop Services is enabled on the host (`Get-Service TermService`)\n- unknown for the exact affected version ranges, as the sources do not list them","plain_action":"","product_name":"","needs_analyst":true,"not_affected_if":["remote-desktop-services-disabled"],"who_is_affected":"Windows machines running Remote Desktop Services, most relevant on multi-user servers and terminal servers where several accounts log on. The sources do not list affected versions or the required account type beyond 'authorized attacker'. Single-user machines with no other accounts are lower risk.","user_interaction":"unknown","product_ecosystem":"","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.000741,"input_tokens":4499,"output_tokens":582,"severity_before":"high"},"analyst_status":"queued","analyst_note":"Find the Microsoft security update guide entry for CVE-2026-122166 to confirm affected Windows builds and the patch.","search":"'-122166':16A,19A '-2026':15A,18A '7.8':66B 'account':45B 'admin':12A 'allow':77C 'alreadi':41B 'attack':39B,80C 'author':44B,79C 'base':29B,69C 'buffer':30B,70C 'cve':14A,17A 'cvss':63B 'describ':54B 'desktop':3A,23B,35B,75C 'elev':82C 'escal':60B 'gain':11A 'infrastructur':20B 'let':7A,37B 'local':9A,58B,84C 'machin':48B 'overflow':6A,31B,71C 'privileg':51B,59B,83C 'rais':49B 'remot':2A,22B,34B,74C 'remote-desktop-servic':21B 'right':13A 'score':64B 'servic':4A,24B,36B,76C 'sourc':53B 'stack':5A,28B,68C 'stack-bas':27B,67C 'user':10A 'window':1A,25B,33B,73C","nicknames":[],"mitigations":[],"who_affected":"Windows machines running Remote Desktop Services, most relevant on multi-user servers and terminal servers where several accounts log on. The sources do not list affected versions or the required account type beyond 'authorized attacker'. Single-user machines with no other accounts are lower risk.","tier":"B","verified":{},"analyst_revisit_at":null,"fix_status":"none","audience":"businesses","plain_action":null,"pkeys":[],"ptokens":[],"labels":["high","infrastructure","remotedesktopservices","windows"],"campaign_type":null,"search_a":"'-122166':16A,19A '-2026':15A,18A 'admin':12A 'cve':14A,17A 'desktop':3A 'gain':11A 'let':7A 'local':9A 'overflow':6A 'remot':2A 'right':13A 'servic':4A 'stack':5A 'user':10A 'window':1A","search_b":"'7.8':66B 'account':45B 'alreadi':41B 'attack':39B 'author':44B 'base':29B 'buffer':30B 'cvss':63B 'describ':54B 'desktop':23B,35B 'escal':60B 'infrastructur':20B 'let':37B 'local':58B 'machin':48B 'overflow':31B 'privileg':51B,59B 'rais':49B 'remot':22B,34B 'remote-desktop-servic':21B 'score':64B 'servic':24B,36B 'sourc':53B 'stack':28B 'stack-bas':27B 'window':25B,33B","search_c":"'allow':77C 'attack':80C 'author':79C 'base':69C 'buffer':70C 'desktop':75C 'elev':82C 'local':84C 'overflow':71C 'privileg':83C 'remot':74C 'servic':76C 'stack':68C 'stack-bas':67C 'window':73C","cause_entry":null,"cause_path":null,"disclosures_checked_at":null,"first_public_at":"2026-11-10T19:20:33+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cvss_by":"secure@microsoft.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-122166","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-122166","severity":null,"published_at":"2026-11-10T19:20:33+00:00","modified_at":"2026-11-10T19:20:33+00:00","first_seen_at":"2026-11-10T19:25:10+00:00","fetched_at":"2026-11-10T19:25:10+00:00","note":null}],"documents":[],"disclosures":[],"exploit_sources":[],"notice":"Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai"}