{"id":"CVE-2026-93636","kind":"vulnerability","aliases":["CVE-2026-93636"],"related":[],"title":"Zimbra: authenticated users can read hidden calendar resource attributes via LDAP injection","description":"An LDAP filter injection vulnerability in Zimbra Collaboration Suite (ZCS) allows an authenticated user to query otherwise unreturned attributes of calendar resources through SearchCalendarResourcesRequest. Zimbra escapes search values but inserts the supplied attribute names directly into LDAP filter expressions without validation. An attacker can inject additional conditions and use repeated matching queries to recover readable resource attributes such as internal mailbox hostnames and mail transport routes. The search remains restricted to calendar-resource objects and the LDAP service account's access rights. ZCS 10.1.16 and 10.1.21 are affected.","summary":"An authenticated Zimbra Collaboration Suite user can inject LDAP filter conditions through the attribute names in SearchCalendarResourcesRequest. Repeated matching queries let them recover readable calendar resource attributes such as internal mailbox hostnames and mail transport routes.","severity":"medium","cvss":4.3,"epss":0.00306,"exploited":false,"exploited_at":null,"products":[],"ecosystems":[],"tags":["email","ldap","package","self-hosted","zimbra"],"not_affected_if":["no-zimbra","unaffected-version"],"how_to_check":"- Check the installed ZCS version with `su - zimbra -c \"zmcontrol -v\"`; versions 10.1.16 and 10.1.21 are affected.\n- unknown for other checks; the sources do not describe log or configuration indicators.","fix":"- Upgrade Zimbra Collaboration Suite to a release that includes the fix for this issue; the sources do not name the fixed version.\n- unknown for a workaround; the sources do not give one.","status":"open","published_at":"2026-10-23T14:17:57+00:00","first_seen_at":"2026-10-23T21:57:34+00:00","triaged_at":"2026-10-25T04:37:16+00:00","updated_at":"2026-10-25T12:38:49+00:00","category":"package","confidence":0.7,"triage":{"at":"2026-10-25T04:37:16Z","model":"claude-haiku-5-5","output":{"fix":"- Upgrade Zimbra Collaboration Suite to a release that includes the fix for this issue; the sources do not name the fixed version.\n- unknown for a workaround; the sources do not give one.","reach":"internet","title":"Zimbra: authenticated users can read hidden calendar resource attributes via LDAP injection","impact":"low","summary":"An authenticated Zimbra Collaboration Suite user can inject LDAP filter conditions through the attribute names in SearchCalendarResourcesRequest. Repeated matching queries let them recover readable calendar resource attributes such as internal mailbox hostnames and mail transport routes.","category":"package","nicknames":[],"who_cares":["zimbra","self-hosted","email","ldap"],"confidence":0.7,"needs_auth":"yes","worst_case":"Authenticated user reads hidden calendar resource mailbox hostnames and routes.","analyst_note":"Find the Zimbra advisory and the fixed version for 10.1.16 and 10.1.21 at the NVD entry linked in the sources.","how_to_check":"- Check the installed ZCS version with `su - zimbra -c \"zmcontrol -v\"`; versions 10.1.16 and 10.1.21 are affected.\n- unknown for other checks; the sources do not describe log or configuration indicators.","needs_analyst":true,"not_affected_if":["unaffected-version","no-zimbra"],"who_is_affected":"Zimbra Collaboration Suite deployments on the affected versions are exposed, and the attacker needs a valid user account on the server. Sites that run no ZCS, or that run a version outside the listed affected releases, can skip it. The sources do not say whether managed hosting changes exposure.","user_interaction":"no","needs_special_setup":"unknown","severity_if_unknown":"medium"},"cost_usd":0.00066,"input_tokens":3443,"output_tokens":631,"severity_before":"medium"},"analyst_status":null,"analyst_note":null,"search":"'-2026':14A,17A '-93636':15A,18A '10.1.16':146C '10.1.21':148C 'access':143C 'account':141C 'addit':107C 'affect':150C 'allow':72C 'attack':104C 'attribut':9A,39B,52B,80C,94C,118C 'authent':2A,27B,74C 'calendar':7A,50B,82C,134C 'calendar-resourc':133C 'collabor':29B,69C 'condit':36B,108C 'cve':13A,16A 'direct':96C 'email':19B 'escap':87C 'express':100C 'filter':35B,64C,99C 'hidden':6A 'host':24B 'hostnam':57B,123C 'inject':12A,33B,65C,106C 'insert':91C 'intern':55B,121C 'ldap':11A,20B,34B,63C,98C,139C 'let':46B 'mail':59B,125C 'mailbox':56B,122C 'match':44B,112C 'name':40B,95C 'object':136C 'otherwis':78C 'packag':21B 'queri':45B,77C,113C 'read':5A 'readabl':49B,116C 'recov':48B,115C 'remain':130C 'repeat':43B,111C 'resourc':8A,51B,83C,117C,135C 'restrict':131C 'right':144C 'rout':61B,127C 'search':88C,129C 'searchcalendarresourcesrequest':42B,85C 'self':23B 'self-host':22B 'servic':140C 'suit':30B,70C 'suppli':93C 'transport':60B,126C 'unreturn':79C 'use':110C 'user':3A,31B,75C 'valid':102C 'valu':89C 'via':10A 'vulner':66C 'without':101C 'zcs':71C,145C 'zimbra':1A,25B,28B,68C,86C","nicknames":[],"mitigations":[],"who_affected":"Zimbra Collaboration Suite deployments on the affected versions are exposed, and the attacker needs a valid user account on the server. Sites that run no ZCS, or that run a version outside the listed affected releases, can skip it. The sources do not say whether managed hosting changes exposure.","tier":"C","verified":{},"analyst_revisit_at":null,"first_public_at":"2026-10-23T14:17:57+00:00","kev":null,"cvss_vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N","cvss_by":"cve@rapid7.com","poc_count":0,"sources":[{"source":"nvd","external_id":"CVE-2026-93636","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-93636","severity":null,"published_at":"2026-10-23T14:17:57+00:00","modified_at":"2026-10-23T16:44:17+00:00","first_seen_at":"2026-10-23T21:57:34+00:00","fetched_at":"2026-10-23T22:29:03+00:00","note":null},{"source":"epss","external_id":"CVE-2026-93636","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-93636","severity":null,"published_at":null,"modified_at":null,"first_seen_at":"2026-10-25T12:38:49+00:00","fetched_at":"2026-10-25T12:38:49+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"}