Zimbra Collaboration Suite LDAP Filter Injection via Calendar Resource Attribute Name
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.
- Products
- Zimbra Collaboration Suite
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-93636
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 2 Nov 2026, 09:51 UTC · Revision 2
Source evidence
Zimbra Collaboration Suite LDAP Filter Injection via Calendar Resource Attribute Name
core-cve · Original sourcePublished 23 Oct 2026, 13:27 UTC
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.
cve:CVE-2026-93636
Zimbra Collaboration Suite
Fixed versions: Not specified
Complete source record
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