{"id":"CVE-2026-108140","kind":"vulnerability","aliases":["CVE-2026-108140"],"related":[],"title":"Backup server: restore role can write files outside target path","description":"A vulnerability allowing an authenticated user with the Restore Operator role, who also controls the contents of a backed-up NAS share, to write attacker-controlled files to an arbitrary path on the backup server through relative path traversal.","summary":"An authenticated user with the Restore Operator role who also controls the contents of a backed-up NAS share can use relative path traversal to write attacker-controlled files to an arbitrary path on the backup server. The sources do not name the product, so the exact impact beyond arbitrary file write is unknown.","severity":"medium","cvss":5.9,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["backup-server","infrastructure","nas","restore-operator"],"not_affected_if":["no-restore-operator-role"],"how_to_check":"- unknown","fix":"- unknown","status":"open","published_at":"2026-10-27T17:16:57+00:00","first_seen_at":"2026-10-27T17:32:45+00:00","triaged_at":"2026-10-27T17:34:52+00:00","updated_at":"2026-10-27T17:34:52+00:00","category":"infrastructure","confidence":0.4,"triage":{"at":"2026-10-27T17:34:52Z","model":"claude-haiku-5-5","output":{"fix":"- unknown","reach":"network","title":"Backup server: restore role can write files outside target path","impact":"high","summary":"An authenticated user with the Restore Operator role who also controls the contents of a backed-up NAS share can use relative path traversal to write attacker-controlled files to an arbitrary path on the backup server. The sources do not name the product, so the exact impact beyond arbitrary file write is unknown.","category":"infrastructure","nicknames":[],"who_cares":["backup-server","nas","restore-operator"],"confidence":0.4,"needs_auth":"yes","worst_case":"Attacker writes arbitrary files to arbitrary paths on backup server","analyst_note":"Identify the affected backup product and fixed version from the NVD entry at https://nvd.nist.gov/vuln/detail/CVE-2026-108140.","how_to_check":"- unknown","needs_analyst":true,"not_affected_if":["no-restore-operator-role"],"who_is_affected":"Teams running the backup server that restores data from NAS shares where a Restore Operator role exists and the share contents can be controlled by a user. The sources do not name the vendor or affected versions, so exposure cannot be confirmed from this text. Teams without a Restore Operator role or without NAS-sourced backups are unlikely to be exposed.","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"medium"},"cost_usd":0.000572,"input_tokens":3289,"output_tokens":486,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-108140':13A,16A '-2026':12A,15A 'allow':83C 'also':34B,93C 'arbitrari':58B,76B,112C 'attack':53B,107C 'attacker-control':52B,106C 'authent':26B,85C 'back':41B,100C 'backed-up':40B,99C 'backup':1A,18B,62B,116C 'backup-serv':17B 'beyond':75B 'content':37B,96C 'control':35B,54B,94C,108C 'cve':11A,14A 'exact':73B 'file':7A,55B,77B,109C 'impact':74B 'infrastructur':20B 'name':68B 'nas':21B,43B,102C 'oper':24B,31B,90C 'outsid':8A 'path':10A,48B,59B,113C,120C 'product':70B 'relat':47B,119C 'restor':3A,23B,30B,89C 'restore-oper':22B 'role':4A,32B,91C 'server':2A,19B,63B,117C 'share':44B,103C 'sourc':65B 'target':9A 'travers':49B,121C 'unknown':80B 'use':46B 'user':27B,86C 'vulner':82C 'write':6A,51B,78B,105C","nicknames":[],"mitigations":[],"who_affected":"Teams running the backup server that restores data from NAS shares where a Restore Operator role exists and the share contents can be controlled by a user. The sources do not name the vendor or affected versions, so exposure cannot be confirmed from this text. Teams without a Restore Operator role or without NAS-sourced backups are unlikely to be exposed.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-27T17:16:57+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:N/VC:N/VI:H/VA:L/SC:N/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":"support@hackerone.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-108140","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-108140","severity":null,"published_at":"2026-10-27T17:16:57+00:00","modified_at":"2026-10-27T17:16:57+00:00","first_seen_at":"2026-10-27T17:32:45+00:00","fetched_at":"2026-10-27T17:32:45+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"}