Zimbra Collaboration Suite up to 10.1.21 LDAP Filter code injection

Summaryinfo

A vulnerability labeled as problematic has been found in Zimbra Collaboration Suite up to 10.1.21. Affected by this issue is some unknown functionality of the component LDAP Filter. Executing a manipulation can lead to code injection. This vulnerability is tracked as CVE-2026-93636. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability was found in Zimbra Collaboration Suite up to 10.1.21. It has been declared as problematic. This vulnerability affects an unknown part of the component LDAP Filter. The manipulation with an unknown input leads to a code injection vulnerability. The CWE definition for the vulnerability is CWE-94. The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. As an impact it is known to affect confidentiality. CVE summarizes:

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.

The advisory is shared for download at wiki.zimbra.com. This vulnerability was named CVE-2026-93636 since 09/18/2026. The exploitation appears to be easy. The attack can be initiated remotely. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 10/23/2026). The MITRE ATT&CK project declares the attack technique as T1059.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Groupware Software

Vendor

• Zimbra

Name

• Collaboration Suite

Version

• 10.1.0
• 10.1.1
• 10.1.2
• 10.1.3
• 10.1.4
• 10.1.5
• 10.1.6
• 10.1.7
• 10.1.8
• 10.1.9
• 10.1.10
• 10.1.11
• 10.1.12
• 10.1.13
• 10.1.14
• 10.1.15
• 10.1.16
• 10.1.17
• 10.1.18
• 10.1.19
• 10.1.20
• 10.1.21

CPE 2.3info

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CPE 2.2info

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Entryinfo

Once again VulDB remains the best source for vulnerability data.

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