{"id":"CVE-2026-111383","kind":"vulnerability","aliases":["CVE-2026-111383"],"related":[],"title":"Nezha: unbounded WebSocket connections let logged-in users exhaust server resources","description":"Nezha from 2.0.13 before 2.3.15 contains a resource exhaustion vulnerability that allows authenticated users to open unbounded concurrent connections to the /api/v1/ws/transfer WebSocket endpoint. Attackers can hold thousands of subscriptions created by ServerTransferClass.Subscribe without limits, exhausting file descriptors, memory, and goroutines and blocking agent gRPC reconnections.","summary":"Nezha versions from 2.0.13 before 2.3.15 do not limit concurrent connections to the /api/v1/ws/transfer WebSocket endpoint. An authenticated user can open thousands of subscriptions, exhausting file descriptors, memory and goroutines and blocking agent gRPC reconnections.","severity":"high","cvss":7.1,"epss":null,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["monitoring","nezha","other","self-hosted"],"not_affected_if":["version-2.3.15-or-later"],"how_to_check":"- Check the running Nezha dashboard version and confirm whether it is `2.0.13` or later but below `2.3.15`\n- unknown whether the sources give a configuration check","fix":"- Upgrade Nezha to `2.3.15` or later\n- unknown whether the sources name a workaround","status":"open","published_at":"2026-10-16T03:18:05+00:00","first_seen_at":"2026-10-23T21:57:12+00:00","triaged_at":"2026-10-25T03:36:49+00:00","updated_at":"2026-10-25T03:36:49+00:00","category":"other","confidence":0.6,"triage":{"at":"2026-10-25T03:36:49Z","model":"claude-haiku-5-5","output":{"fix":"- Upgrade Nezha to `2.3.15` or later\n- unknown whether the sources name a workaround","reach":"internet","title":"Nezha: unbounded WebSocket connections let logged-in users exhaust server resources","impact":"medium","summary":"Nezha versions from 2.0.13 before 2.3.15 do not limit concurrent connections to the /api/v1/ws/transfer WebSocket endpoint. An authenticated user can open thousands of subscriptions, exhausting file descriptors, memory and goroutines and blocking agent gRPC reconnections.","category":"other","nicknames":[],"who_cares":["nezha","self-hosted","monitoring"],"confidence":0.6,"needs_auth":"yes","worst_case":"Authenticated user degrades the dashboard server, blocking agent reconnections","analyst_note":"Confirm whether the NVD entry and the upstream Nezha release notes give a workaround or config setting before 2.3.15, and whether the endpoint is reachable by non-admin accounts.","how_to_check":"- Check the running Nezha dashboard version and confirm whether it is `2.0.13` or later but below `2.3.15`\n- unknown whether the sources give a configuration check","needs_analyst":true,"not_affected_if":["version-2.3.15-or-later"],"who_is_affected":"Teams that self-host the Nezha monitoring dashboard in versions from `2.0.13` before `2.3.15` are exposed, since the flaw is in the dashboard's WebSocket transfer endpoint. Exposure requires an authenticated user account on the dashboard. Installations already on `2.3.15` or later are not affected.","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"unknown"},"cost_usd":0.000643,"input_tokens":3373,"output_tokens":611,"severity_before":"high"},"analyst_status":null,"analyst_note":null,"search":"'-111383':15A,18A '-2026':14A,17A '/api/v1/ws/transfer':38B,81C '2.0.13':28B,62C '2.3.15':30B,64C 'agent':57B,103C 'allow':71C 'attack':84C 'authent':42B,72C 'block':56B,102C 'concurr':34B,77C 'connect':4A,35B,78C 'contain':65C 'creat':90C 'cve':13A,16A 'descriptor':51B,97C 'endpoint':40B,83C 'exhaust':10A,49B,68C,95C 'file':50B,96C 'goroutin':54B,100C 'grpc':58B,104C 'hold':86C 'host':24B 'let':5A 'limit':33B,94C 'log':7A 'logged-in':6A 'memori':52B,98C 'monitor':19B 'nezha':1A,20B,25B,60C 'open':45B,75C 'reconnect':59B,105C 'resourc':12A,67C 'self':23B 'self-host':22B 'server':11A 'servertransferclass.subscribe':92C 'subscript':48B,89C 'thousand':46B,87C 'unbound':2A,76C 'user':9A,43B,73C 'version':26B 'vulner':69C 'websocket':3A,39B,82C 'without':93C","nicknames":[],"mitigations":[],"who_affected":"Teams that self-host the Nezha monitoring dashboard in versions from `2.0.13` before `2.3.15` are exposed, since the flaw is in the dashboard's WebSocket transfer endpoint. Exposure requires an authenticated user account on the dashboard. Installations already on `2.3.15` or later are not affected.","tier":"B","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-16T03:18:05+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/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":"disclosure@vulncheck.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-111383","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-111383","severity":null,"published_at":"2026-10-16T03:18:05+00:00","modified_at":"2026-10-16T17:17:33+00:00","first_seen_at":"2026-10-23T21:57:12+00:00","fetched_at":"2026-10-23T22:28:54+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"}