{"id":"CVE-2026-111656","kind":"vulnerability","aliases":["CVE-2026-111656"],"related":[],"title":"ChatWiki: authenticated users read and reorder other tenants' form filters","description":"ChatWiki through 2.9.6 contains an insecure direct object reference vulnerability that allows authenticated users to access another tenant's form filters by supplying arbitrary form_id values. Attackers can send sequential form_id values to getFormFilterList, getFormFilterInfo and updateFormFilterSort to read filter rules and overwrite another tenant's filter sort order.","summary":"ChatWiki through 2.9.6 does not check ownership of form_id values, so a logged-in user can supply another tenant's form_id. An attacker can read that tenant's filter rules and overwrite its filter sort order.","severity":"medium","cvss":5.4,"epss":null,"exploited":false,"exploited_at":null,"products":[{"name":"chatwiki","fixed":[],"affected":"<= 2.9.6","ecosystem":"vendor"}],"ecosystems":[],"tags":["ai-tooling","chatwiki","cwe-639","idor","multi-tenant","self-hosted"],"not_affected_if":["auth-required","single-tenant-deployment"],"how_to_check":"Self-hosted ChatWiki <= 2.9.6 (multi-tenant): in internal/app/chatwiki/business/manage/form.go, GetFormFilterList, GetFormFilterInfo and UpdateFormFilterSort have no admin_user_id check on the form lookup. Test with a user from tenant A: call GET /manage/getFormFilterList?form_id=<tenant B form id>. If it returns filters instead of a no_data error, you are exposed. Check access logs for sequential form_id values on getFormFilterList, getFormFilterInfo and updateFormFilterSort.","fix":"No fixed release known: 2.9.6 is the latest release and is affected. Watch github.com/zhimaAi/chatwiki/releases for a later version. Until then, restrict accounts to trusted users, or block /manage/updateFormFilterSort, getFormFilterList and getFormFilterInfo at the reverse proxy if you don't use form filters.","status":"open","published_at":"2026-10-16T18:17:46+00:00","first_seen_at":"2026-10-23T21:57:13+00:00","triaged_at":"2026-10-25T04:18:21+00:00","updated_at":"2026-10-25T04:19:19+00:00","category":"ai-tooling","confidence":0.75,"triage":{"at":"2026-10-25T04:18:21Z","model":"claude-haiku-5-5","output":{"fix":"unknown","reach":"internet","title":"ChatWiki: authenticated users read and reorder other tenants' form filters","impact":"medium","summary":"ChatWiki through 2.9.6 does not check ownership of form_id values, so a logged-in user can supply another tenant's form_id. An attacker can read that tenant's filter rules and overwrite its filter sort order.","category":"ai-tooling","nicknames":[],"who_cares":["chatwiki","self-hosted","multi-tenant"],"confidence":0.7,"needs_auth":"yes","worst_case":"Other tenants' filter rules readable and sort order overwritten","analyst_note":"Check the ChatWiki project or NVD entry for a fixed release version and whether the form filter endpoints are reachable by any tenant user.","how_to_check":"unknown","needs_analyst":true,"not_affected_if":["single-tenant-deployment","auth-required"],"who_is_affected":"unknown","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"medium"},"cost_usd":0.000519,"input_tokens":3345,"output_tokens":369,"severity_before":"medium"},"analyst_status":"done","analyst_note":"Check the ChatWiki project or NVD entry for a fixed release version and whether the form filter endpoints are reachable by any tenant user.","search":"'-111656':13A,16A '-2026':12A,15A '-639':23B '2.9.6':33B,72C 'access':85C 'ai':19B 'ai-tool':18B 'allow':81C 'anoth':50B,86C,115C 'arbitrari':93C 'attack':56B,97C 'authent':2A,82C 'chatwiki':1A,17A,21B,31B,70C 'check':36B 'contain':73C 'cve':11A,14A 'cwe':22B 'direct':76C 'filter':10A,62B,67B,90C,111C,118C 'form':9A,39B,53B,89C,94C,101C 'getformfilterinfo':106C 'getformfilterlist':105C 'host':30B 'id':40B,54B,95C,102C 'idor':24B 'insecur':75C 'log':45B 'logged-in':44B 'multi':26B 'multi-ten':25B 'object':77C 'order':69B,120C 'overwrit':65B,114C 'ownership':37B 'read':4A,58B,110C 'refer':78C 'reorder':6A 'rule':63B,112C 'self':29B 'self-host':28B 'send':99C 'sequenti':100C 'sort':68B,119C 'suppli':49B,92C 'tenant':8A,27B,51B,60B,87C,116C 'tool':20B 'updateformfiltersort':108C 'user':3A,47B,83C 'valu':41B,96C,103C 'vulner':79C","nicknames":[],"mitigations":[],"who_affected":null,"tier":"B","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-16T18:17:46+00:00","kev":null,"cvss_vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/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-2026-111656","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-111656","severity":null,"published_at":"2026-10-16T18:17:46+00:00","modified_at":"2026-10-16T22:17:21+00:00","first_seen_at":"2026-10-23T21:57:13+00:00","fetched_at":"2026-10-23T22:28:55+00:00","note":null},{"source":"analyst","external_id":"CVE-2026-111656:812","url":null,"severity":null,"published_at":"2026-10-25T04:19:19+00:00","modified_at":"2026-10-25T04:19:19+00:00","first_seen_at":"2026-10-25T04:19:19+00:00","fetched_at":"2026-10-25T04:19:19+00:00","note":"Read VulnCheck advisory and researcher's write-up (hackmd, source review of v2.9.5; CVE says through 2.9.6). No vendor advisory or fixed release found: v2.9.6 (16 Oct) is latest and listed affected. No exploitation or PoC found; researcher's requests were unexecuted. Nothing marked verified."}],"documents":[{"id":3386,"url":"https://www.vulncheck.com/advisories/chatwiki-through-2.9.6-cross-tenant-idor-via-form-filter-management-endpoints","title":"VulnCheck: ChatWiki through 2.9.6 Cross-Tenant IDOR via Form Filter Management Endpoints","kind":"advisory","source":"analyst","text":null,"published_at":null,"relation":"advisory","confidence":null,"note":null},{"id":3387,"url":"https://hackmd.io/@hieuPenguinnn/chatwiki-form-filter-cross-tenant-idor","title":"hieuPenguinnn: ChatWiki form filter handlers skip tenant ownership check","kind":"blog","source":"analyst","text":null,"published_at":null,"relation":"describes","confidence":null,"note":null},{"id":3388,"url":"https://github.com/zhimaAi/chatwiki/releases","title":"zhimaAi/chatwiki releases (latest v2.9.6, 16 Oct)","kind":"release","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"}