CVE-2026-93636

Zimbra Collaboration Suite LDAP Filter Injection via Calendar Resource Attribute Name

MEDIUM
4.3
CVSS Score
Published: October 23, 2026 at 01:27 PM UTC
Updated: October 28, 2026 at 09:15 PM UTC
1 product affected across 1 vendorZimbra Collaboration Suite

Using Zimbra Collaboration Suite by Zimbra?

Get instant alerts when new vulnerabilities affect Zimbra Collaboration Suite - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
MEDIUM4.3
Exploit prediction
EPSS 0.3%
SSVC
No known exploit

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (2)

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

4.3MEDIUMrapid7
Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
LOW
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-90

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card