{"id":"CVE-2026-106781","kind":"vulnerability","aliases":["CVE-2026-106781"],"related":[],"title":"WCH CH340/CH341 Windows driver installer lets local users escalate privileges","description":"An issue in WCH CH340/CH341 USB-to-Serial Windows Driver setup package CH341SER.EXE version 4.0 allows a local attacker to escalate privileges.","summary":"The WCH CH340/CH341 USB-to-serial Windows driver setup package CH341SER.EXE version 4.0 contains a flaw that lets a local attacker escalate privileges. The sources do not describe the exact mechanism.","severity":"unknown","cvss":null,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["hardware-tooling","infrastructure","usb-serial","windows"],"not_affected_if":["package-not-installed"],"how_to_check":"- Look for CH341SER.EXE on Windows machines and check its file version with the file properties dialog\n- unknown for further checks: the sources do not say how the version is reported or which installed driver files to compare","fix":"- Move off CH341SER.EXE version 4.0 to a newer vendor driver release from WCH\n- unknown for the exact fixed version: the sources do not say","status":"open","published_at":"2026-10-26T15:16:35+00:00","first_seen_at":"2026-10-26T16:02:25+00:00","triaged_at":"2026-10-26T16:04:17+00:00","updated_at":"2026-10-26T16:04:17+00:00","category":"infrastructure","confidence":0.5,"triage":{"at":"2026-10-26T16:04:17Z","model":"claude-haiku-5-5","output":{"fix":"- Move off CH341SER.EXE version 4.0 to a newer vendor driver release from WCH\n- unknown for the exact fixed version: the sources do not say","reach":"local","title":"WCH CH340/CH341 Windows driver installer lets local users escalate privileges","impact":"high","summary":"The WCH CH340/CH341 USB-to-serial Windows driver setup package CH341SER.EXE version 4.0 contains a flaw that lets a local attacker escalate privileges. The sources do not describe the exact mechanism.","category":"infrastructure","nicknames":[],"who_cares":["windows","usb-serial","hardware-tooling"],"confidence":0.5,"needs_auth":"yes","worst_case":"local user gains higher privileges on the Windows machine","analyst_note":"Check the NVD entry and WCH's vendor page for the mechanism, the fixed version and any advisory text on the CH341SER.EXE 4.0 package.","how_to_check":"- Look for CH341SER.EXE on Windows machines and check its file version with the file properties dialog\n- unknown for further checks: the sources do not say how the version is reported or which installed driver files to compare","needs_analyst":true,"not_affected_if":["package-not-installed"],"who_is_affected":"Windows machines where the CH340/CH341 driver setup package version 4.0 was run or kept, typically developer workstations and lab or industrial PCs that use USB-to-serial adapters. Systems that never installed this package can skip it. The sources do not describe the exact trigger.","user_interaction":"unknown","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.000614,"input_tokens":3286,"output_tokens":570,"severity_before":"unknown"},"analyst_status":null,"analyst_note":null,"search":"'-106781':13A,16A '-2026':12A,15A '4.0':38B,72C 'allow':73C 'attack':46B,76C 'ch340/ch341':2A,27B,61C 'ch341ser.exe':36B,70C 'contain':39B 'cve':11A,14A 'describ':53B 'driver':4A,33B,67C 'escal':9A,47B,78C 'exact':55B 'flaw':41B 'hardwar':18B 'hardware-tool':17B 'infrastructur':20B 'instal':5A 'issu':58C 'let':6A,43B 'local':7A,45B,75C 'mechan':56B 'packag':35B,69C 'privileg':10A,48B,79C 'serial':23B,31B,65C 'setup':34B,68C 'sourc':50B 'tool':19B 'usb':22B,29B,63C 'usb-seri':21B 'usb-to-seri':28B,62C 'user':8A 'version':37B,71C 'wch':1A,26B,60C 'window':3A,24B,32B,66C","nicknames":[],"mitigations":[],"who_affected":"Windows machines where the CH340/CH341 driver setup package version 4.0 was run or kept, typically developer workstations and lab or industrial PCs that use USB-to-serial adapters. Systems that never installed this package can skip it. The sources do not describe the exact trigger.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-26T15:16:35+00:00","kev":null,"cvss_vector":null,"cvss_by":null,"poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-106781","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-106781","severity":null,"published_at":"2026-10-26T15:16:35+00:00","modified_at":"2026-10-26T15:16:35+00:00","first_seen_at":"2026-10-26T16:02:25+00:00","fetched_at":"2026-10-26T16:02:25+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"}