A reflected cross-site scripting vulnerability in the login page of Zimbra Collaboration Suite (ZCS) allows an unauthenticated attacker to execute JavaScript through the zrememberme parameter. A crafted relogin URL selects a two-factor error display that inserts the parameter into a hidden input attribute without HTML encoding. A victim who opens the URL receives attacker-controlled script and page content under the legitimate Zimbra origin, allowing credential capture through a replacement login form. The relogin path logs out an existing session before rendering the payload, so the demonstrated attack does not inherit that session's mailbox access. ZCS 10.1.16 and 10.1.17 are affected.

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.

A cross-site request forgery vulnerability in the OAuth extension of Zimbra Collaboration Suite (ZCS) Network Edition allows an attacker to link an attacker-controlled external account to a victim's mailbox. The OAuth callback does not bind its state value or authorization code to the initiating Zimbra session and instead selects the destination mailbox from the browser's current authentication cookie. On a deployment with the provider configured, an attacker can induce a signed-in victim to load a callback containing a fresh code for the attacker's provider account. This creates a persistent data source that imports attacker-controlled contacts or events. With bidirectional CalDAV synchronization, appointments subsequently created or edited in the linked calendar are also disclosed to the attacker. ZCS 10.1.16 and 10.1.20 are affected.

In Zimbra Collaboration (ZCS) before 10.1.17, weak cryptographic key generation vulnerability exists in the OnlyOffice integration. The zimbraDocumentEditingJwtSecret is generated using an insecure random number generator, resulting in insufficient entropy. An attacker who obtains a JWT signed with the generated secret may be able to recover the JWT signing secret through offline brute-force, potentially enabling JWT forgery.

In Zimbra Collaboration (ZCS) before 10.1.17, a Cross-Site Request Forgery (CSRF) vulnerability exists in the Exchange Web Services (EWS) endpoint of Zimbra Collaboration (ZCS) due to insufficient validation of request content types. An attacker can exploit this vulnerability by causing an authenticated user to submit a crafted request, potentially allowing unauthorized actions to be performed on behalf of the victim.

In Zimbra Collaboration before 10.1.17, a local file inclusion (LFI) vulnerability exists in the Zimbra Classic Web Client due to improper validation of the fu request parameter. An unauthenticated attacker can exploit this vulnerability by supplying a crafted path, potentially allowing unauthorized disclosure of protected files, such as WEB-INF/web.xml, within the web application directory. This occurs in the Forward servlet.

In Zimbra Collaboration (ZCS) before 10.1.17, a path traversal vulnerability exists in the Zimbra Briefcase document editing functionality due to improper validation of the packages parameter. An authenticated attacker can exploit this vulnerability by supplying a crafted path traversal sequence, potentially allowing unauthorized disclosure of sensitive files within the web application directory.

In Zimbra Collaboration (ZCS) before 10.1.17, a stored cross-site scripting (XSS) vulnerability exists in the Zimbra Classic Web Client due to insufficient sanitization of specific attachment content during inline preview. An attacker can send a crafted email containing a malicious attachment that, when previewed by a user, executes arbitrary JavaScript within the victim's browser session. Successful exploitation may allow an attacker to perform unauthorized actions on behalf of the victim user, potentially leading to data exfiltration or unauthorized access to sensitive information.

An authorization bypass vulnerability exists in Zimbra Collaboration (ZCS) before 10.1.17 due to improper authorization validation in delegated email sending functionality. An authenticated attacker can send specially crafted SOAP requests to impersonate another user and send emails without possessing the required delegation or send-as permissions. This occurs in the SaveDraftRequest SOAP handler.

A remote code execution vulnerability exists in Zimbra Collaboration (ZCS) before 10.1.20 when the optional zimbra-snmp package is installed and SNMP notifications are enabled. Due to improper sanitization of untrusted input during SNMP notification processing, an unauthenticated attacker can send specially crafted SMTP requests that may result in execution of arbitrary operating system commands as the Zimbra user.

An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1. A Cross-Site Request Forgery (CSRF) vulnerability exists in Zimbra Web Client due to the issuance of authentication tokens without CSRF protection during certain account state transitions. Specifically, tokens generated after operations such as enabling two-factor authentication or changing a password may lack CSRF enforcement. While such a token is active, authenticated SOAP requests that trigger token generation or state changes can be performed without CSRF validation. An attacker could exploit this by inducing a victim to submit crafted requests, potentially allowing sensitive account actions such as disabling two-factor authentication. The issue is mitigated by ensuring CSRF protection is consistently enforced for all issued authentication tokens.

An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1. A stored cross-site scripting (XSS) vulnerability exists in the Zimbra Briefcase feature due to insufficient sanitization of specific uploaded file types. When a user opens a publicly shared Briefcase file containing malicious scripts, the embedded JavaScript executes in the context of the user's session. This allows an attacker to run arbitrary scripts, potentially leading to data exfiltration or other unauthorized actions on behalf of the victim user.

An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1. An XML External Entity (XXE) vulnerability exists in the Zimbra Exchange Web Services (EWS) SOAP interface due to improper handling of XML input. An authenticated attacker can submit crafted XML data that is processed by an XML parser with external entity resolution enabled. Successful exploitation may allow disclosure of sensitive local files from the server.

Zimbra Collaboration (ZCS) 10.0 and 10.1 contains an LDAP injection vulnerability in the Mailbox SOAP service within a FolderAction operation. The application fails to properly sanitize user-supplied input before incorporating it into an LDAP search filter. An authenticated attacker can exploit this issue by sending a crafted SOAP request that manipulates the LDAP query, allowing retrieval of sensitive directory attributes.

An issue was discovered in Zimbra Collaboration (ZCS) 10.0 and 10.1. A cross-site request forgery (CSRF) vulnerability exists in Zimbra Webmail due to improper validation of CSRF tokens. The application accepts CSRF tokens supplied within the request body instead of requiring them through the expected request header. An attacker can exploit this issue by tricking an authenticated user into submitting a crafted request. This may allow unauthorized actions to be performed on behalf of the victim.

Zimbra Collaboration Suite (ZCS) 10.0 and 10.1 contains a reflected cross-site scripting (XSS) vulnerability in the Classic Webmail REST interface (/h/rest). The application fails to properly sanitize user-supplied input, allowing an unauthenticated attacker to inject malicious JavaScript into a crafted URL. When a victim user accesses the link, the injected script executes in the context of the Zimbra webmail application, which could allow the attacker to perform actions on behalf of the victim.

Synacor Zimbra Collaboration Suite (ZCS) contains a cross-site scripting vulnerability in the Classic UI where attackers could abuse Cascading Style Sheets (CSS) @import directives in email HTML.

A Local File Inclusion (LFI) vulnerability exists in the Webmail Classic UI of Zimbra Collaboration (ZCS) 10.0 and 10.1 because of improper handling of user-supplied request parameters in the RestFilter servlet. An unauthenticated remote attacker can craft requests to the /h/rest endpoint to influence internal request dispatching, allowing inclusion of arbitrary files from the WebRoot directory.

An issue was discovered in Zimbra Collaboration (ZCS) 8.8.15 and 9.0 and 10.0 and 10.1. A Cross-Site Scripting (XSS) vulnerability in the Zimbra Classic UI allows attackers to execute arbitrary JavaScript within the user's session, potentially leading to unauthorized access to sensitive information. This issue arises from insufficient sanitization of HTML content, specifically involving crafted tag structures and attribute values that include an @import directive and other script injection vectors. The vulnerability is triggered when a user views a crafted e-mail message in the Classic UI, requiring no additional user interaction.

An issue was discovered in Zimbra Collaboration (ZCS) 9.0.0 before Patch 43, 10.0.x before 10.0.12, 10.1.x before 10.1.4, and 8.8.15 before Patch 47. A Cross-Site Scripting (XSS) vulnerability in the Zimbra Classic UI allows attackers to execute arbitrary JavaScript within the user's session, potentially leading to unauthorized access to sensitive information. This issue arises from insufficient sanitization of HTML content, including malformed <img> tags with embedded JavaScript. The vulnerability is triggered when a user views a specially crafted email in the Classic UI, requiring no additional user interaction.

In Zimbra Collaboration (ZCS) 9.0 through 10.1, a Cross-Site Request Forgery (CSRF) vulnerability exists in the GraphQL endpoint (/service/extension/graphql) of Zimbra webmail due to a lack of CSRF token validation. This allows attackers to perform unauthorized GraphQL operations, such as modifying contacts, changing account settings, and accessing sensitive user data when an authenticated user visits a malicious website.

An issue was discovered in Zimbra Collaboration (ZCS) 9.0 and 10.0 and 10.1. A stored cross-site scripting (XSS) vulnerability exists in the Classic Web Client due to insufficient sanitization of HTML content in ICS files. When a user views an e-mail message containing a malicious ICS entry, its embedded JavaScript executes via an ontoggle event inside a <details> tag. This allows an attacker to run arbitrary JavaScript within the victim's session, potentially leading to unauthorized actions such as setting e-mail filters to redirect messages to an attacker-controlled address. As a result, an attacker can perform unauthorized actions on the victim's account, including e-mail redirection and data exfiltration.

SQL injection vulnerability in the ZimbraSync Service SOAP endpoint in Zimbra Collaboration 10.0.x before 10.0.12 and 10.1.x before 10.1.4 due to insufficient sanitization of a user-supplied parameter. Authenticated attackers can exploit this vulnerability by manipulating a specific parameter in the request, allowing them to inject arbitrary SQL queries that could retrieve email metadata.

SSRF vulnerability in the RSS feed parser in Zimbra Collaboration 9.0.0 before Patch 43, 10.0.x before 10.0.12, and 10.1.x before 10.1.4 allows unauthorized redirection to internal network endpoints.

An issue was discovered in the Webmail Classic UI in Zimbra Collaboration (ZCS) 9.0 and 10.0 and 10.1. A Local File Inclusion (LFI) vulnerability exists in the /h/rest endpoint, allowing authenticated remote attackers to include and access sensitive files in the WebRoot directory. Exploitation requires a valid auth token and involves crafting a malicious request targeting specific file paths.

An issue was discovered in webmail in Zimbra Collaboration (ZCS) through 10.1. An attacker can exploit this vulnerability by creating a folder in the Briefcase module with a malicious payload and sharing it with a victim. When the victim interacts with the folder share notification, the malicious script executes in their browser. This stored Cross-Site Scripting (XSS) vulnerability can lead to unauthorized actions within the victim's session.

An issue was discovered in Zimbra Collaboration (ZCS) through v10.1. A Cross-Site Scripting (XSS) vulnerability exists in one of the endpoints of Zimbra Webmail due to insufficient sanitization of the packages parameter. Attackers can bypass the existing checks by using encoded characters, allowing the injection and execution of arbitrary JavaScript within a victim's session.

An issue was discovered in Zimbra Collaboration (ZCS) through 10.1. A Cross-Site Scripting (XSS) vulnerability in the /h/rest endpoint of the Zimbra webmail and admin panel interfaces allows attackers to execute arbitrary JavaScript in the victim's session. This issue is caused by improper sanitization of user input, leading to potential compromise of sensitive information. Exploitation requires user interaction to access the malicious URL.