{"id":"CVE-2026-43851","kind":"vulnerability","aliases":["CVE-2026-43851"],"related":[],"title":"Authenticated path traversal lets attackers read arbitrary files on system","description":"A path traversal vulnerability could allow an authenticated attacker to read arbitrary files on the system.","summary":"Advantech ADAM-3600 EdgeLink RTU: a path traversal in the project file transfer handler (mod_projectmr, message ID 104 Upload Start) lets an authenticated user use ../ sequences to read any file on the device. Part of a 30-CVE batch fixed in the same update.","severity":"high","cvss":8.2,"epss":null,"exploited":false,"exploited_at":null,"products":[{"name":"ADAM-3600","fixed":["2.8.5.0"],"affected":"< 2.8.5.0","ecosystem":"vendor"}],"ecosystems":[],"tags":["adam-3600","advantech","auth-required","edgelink","ics","other","path-traversal","rtu"],"not_affected_if":["auth-required"],"how_to_check":"Check the ADAM-3600 firmware/EdgeLink version in the device web UI or EdgeLink tooling; versions prior to 2.8.5.0 are affected, and per the vendor's text for this CVE the directory restriction arrives in 2.8.5.1. Also check whether the device's management/proprietary-protocol ports (6001/7001) are reachable from untrusted networks.","fix":"Upgrade ADAM-3600 to firmware 2.8.5.1 or later (CVE record says fixed in 2.8.5.0; vendor's solution for this CVE cites 2.8.5.1, which limits read/write to /tmp and /home/sysuser, or /tmp, /home/sysuser/project, /home/www/xml in the SE edition). Meanwhile keep the device off untrusted networks and rotate credentials.","status":"open","published_at":"2026-10-20T10:17:06+00:00","first_seen_at":"2026-10-23T21:57:20+00:00","triaged_at":"2026-10-25T03:04:14+00:00","updated_at":"2026-10-25T03:34:01+00:00","category":"other","confidence":0.75,"triage":{"at":"2026-10-25T03:04:14Z","model":"claude-haiku-5-5","output":{"fix":"unknown","reach":"unknown","title":"Authenticated path traversal lets attackers read arbitrary files on system","impact":"medium","summary":"A path traversal flaw lets a logged-in user point a file request outside the intended directory. An attacker can read any file the service process can access, such as configuration or credential files.","category":"other","nicknames":[],"who_cares":[],"confidence":0.3,"needs_auth":"yes","worst_case":"Attacker reads arbitrary files on the system, possibly including secrets","analyst_note":"Identify the affected product and versions from the NVD entry at https://nvd.nist.gov/vuln/detail/CVE-2026-43851; the description names no product.","how_to_check":"unknown","needs_analyst":true,"not_affected_if":[],"who_is_affected":"unknown","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"high"},"cost_usd":0.000484,"input_tokens":3244,"output_tokens":319,"severity_before":"high"},"analyst_status":"done","analyst_note":"Identify the affected product and versions from the NVD entry at https://nvd.nist.gov/vuln/detail/CVE-2026-43851; the description names no product.","search":"'-2026':12A,15A '-3600':18A,20B,34B '-43851':13A,16A '104':50B '30':69B 'adam':17A,19B,33B 'advantech':21B,32B 'allow':82C 'arbitrari':7A,88C 'attack':5A,85C 'auth':23B 'auth-requir':22B 'authent':1A,55B,84C 'batch':71B 'could':81C 'cve':11A,14A,70B 'devic':65B 'edgelink':25B,35B 'file':8A,43B,62B,89C 'fix':72B 'handler':45B 'ic':26B 'id':49B 'let':4A,53B 'messag':48B 'mod':46B 'part':66B 'path':2A,29B,38B,78C 'path-travers':28B 'project':42B 'projectmr':47B 'read':6A,60B,87C 'requir':24B 'rtu':31B,36B 'sequenc':58B 'start':52B 'system':10A,92C 'transfer':44B 'travers':3A,30B,39B,79C 'updat':76B 'upload':51B 'use':57B 'user':56B 'vulner':80C","nicknames":[],"mitigations":[],"who_affected":null,"tier":"B","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-20T10:17:06+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","cvss_by":"5f57b9bf-260d-4433-bf07-b6a79e9bb7d4","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-43851","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-43851","severity":null,"published_at":"2026-10-20T10:17:06+00:00","modified_at":"2026-10-20T19:30:59+00:00","first_seen_at":"2026-10-23T21:57:20+00:00","fetched_at":"2026-10-23T22:28:57+00:00","note":null},{"source":"analyst","external_id":"CVE-2026-43851:744","url":null,"severity":null,"published_at":"2026-10-25T03:34:01+00:00","modified_at":"2026-10-25T03:34:01+00:00","first_seen_at":"2026-10-25T03:34:01+00:00","fetched_at":"2026-10-25T03:34:01+00:00","note":"Product identified as Advantech ADAM-3600 EdgeLink RTU (vendor PDF ACIRT-261001 item 23, NN-2026-0012; CVE record: prior to 2.8.5.0). Vendor's own fix text for this item says 2.8.5.1+ restricts file dirs, so 2.8.5.0 vs 2.8.5.1 is unsettled; nothing marked verified. No exploitation or PoC found; no social search done (low-profile ICS)."}],"documents":[{"id":1917,"url":"https://advcloudfiles.advantech.com/cms/de8e2d94-10ab-470e-ac6f-d2e5434f4ec4/Security%20Advisory%20PDF%20File/SECURITY-ADVISORY----ADAM-3600.pdf","title":"Advantech: Vulnerabilities Identified in ADAM-3600 (ACIRT-261001)","kind":"advisory","source":"analyst","text":null,"published_at":null,"relation":"advisory","confidence":null,"note":null},{"id":1913,"url":"https://www.csa.gov.sg/alerts-and-advisories/alerts/al-2026-149","title":"CSA Singapore AL-2026-149: Advantech ADAM-3600 EdgeLink multiple vulnerabilities","kind":"advisory","source":"analyst","text":null,"published_at":null,"relation":"mentions","confidence":null,"note":null}],"notice":"Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai"}