Vulnerabilities

Very large headers can cause resource exhaustion when parsing message. The message-parser normally reads reasonably sized chunks of the message. However, when it feeds them to message-header-parser, it starts building up "full_value" buffer out of the smaller chunks. The full_value buffer has no size limit, so large headers can cause large memory usage. It doesn't matter whether it's a single long header line, or a single header split into multiple lines. This bug exists in all Dovecot versions. Incoming mails typically have some size limits set by MTA, so even largest possible header size may still fit into Dovecot's vsz_limit. So attackers probably can't DoS a victim user this way. A user could APPEND larger mails though, allowing them to DoS themselves (although maybe cause some memory issues for the backend in general). One can implement restrictions on headers on MTA component preceding Dovecot. No publicly available exploits are known.

Having a large number of address headers (From, To, Cc, Bcc, etc.) becomes excessively CPU intensive. With 100k header lines CPU usage is already 12 seconds, and in a production environment we observed 500k header lines taking 18 minutes to parse. Since this can be triggered by external actors sending emails to a victim, this is a security issue. An external attacker can send specially crafted messages that consume target system resources and cause outage. One can implement restrictions on address headers on MTA component preceding Dovecot. No publicly available exploits are known.

Dovecot accepts dot LF DOT LF symbol as end of DATA command. RFC requires that it should always be CR LF DOT CR LF. This causes Dovecot to convert single mail with LF DOT LF in middle, into two emails when relaying to SMTP. Dovecot will split mail with LF DOT LF into two mails. Upgrade to latest released version. No publicly available exploits are known.

Module savepoints could be abused to inject references to malicious code delivered through the same domain. Attackers could perform malicious API requests or extract information from the users account. Exploiting this vulnerability requires temporary access to an account or successful social engineering to make a user follow a prepared link to a malicious account. Please deploy the provided updates and patch releases. The savepoint module path has been restricted to modules that provide the feature, excluding any arbitrary or non-existing modules. No publicly available exploits are known.

E-Mails exported as PDF were stored in a cache that did not consider specific session information for the related user account. Users of the same service node could access other users E-Mails in case they were exported as PDF for a brief moment until caches were cleared. Successful exploitation requires good timing and modification of multiple request parameters. Please deploy the provided updates and patch releases. The cache for PDF exports now takes user session information into consideration when performing authorization decisions. No publicly available exploits are known.

Maliciously crafted E-Mail attachment names could be used to temporarily execute script code in the context of the users browser session. Common user interaction is required for the vulnerability to trigger. Attackers could perform malicious API requests or extract information from the users account. Please deploy the provided updates and patch releases. We now use safer methods of handling external content when embedding attachment information to the web interface. No publicly available exploits are known.

Content-ID based embedding of resources in E-Mails could be abused to trigger client-side script code when using the "show more" option. Attackers could perform malicious API requests or extract information from the users account. Exploiting the vulnerability requires user interaction. Please deploy the provided updates and patch releases. CID replacement has been hardened to omit invalid identifiers. No publicly available exploits are known.

E-Mail containing malicious display-name information could trigger client-side script execution when using specific mobile devices. Attackers could perform malicious API requests or extract information from the users account. Please deploy the provided updates and patch releases. We now use safer methods of handling external content when embedding displayname information to the web interface. No publicly available exploits are known.

RSS feeds that contain malicious data- attributes could be abused to inject script code to a users browser session when reading compromised RSS feeds or successfully luring users to compromised accounts. Attackers could perform malicious API requests or extract information from the users account. Please deploy the provided updates and patch releases. Potentially malicious attributes now get removed from external RSS content. No publicly available exploits are known.

Upsell advertisement information of an account can be manipulated to execute script code in the context of the users browser session. To exploit this an attacker would require temporary access to a users account or an successful social engineering attack to lure users to maliciously configured accounts. Attackers could perform malicious API requests or extract information from the users account. Please deploy the provided updates and patch releases. Sanitization of user-defined upsell content has been improved. No publicly available exploits are known.

Upsell shop information of an account can be manipulated to execute script code in the context of the users browser session. To exploit this an attacker would require temporary access to a users account or an successful social engineering attack to lure users to maliciously configured accounts. Attackers could perform malicious API requests or extract information from the users account. Please deploy the provided updates and patch releases. Sanitization of user-defined upsell content has been improved. No publicly available exploits are known.

Embedded content references at tasks could be used to temporarily execute script code in the context of the users browser session. To exploit this an attacker would require temporary access to the users account, access to another account within the same context or an successful social engineering attack to make users import external content. Attackers could perform malicious API requests or extract information from the users account. Please deploy the provided updates and patch releases. Sanitization of user-generated content has been improved. No publicly available exploits are known.

References to the "app loader" functionality could contain redirects to unexpected locations. Attackers could forge app references that bypass existing safeguards to inject malicious script code. Please deploy the provided updates and patch releases. References to apps are now controlled more strict to avoid relative references. No publicly available exploits are known.

Processing of user-defined mail search expressions is not limited. Availability of OX App Suite could be reduced due to high processing load. Please deploy the provided updates and patch releases. Processing time of mail search expressions now gets monitored, and the related request is terminated if a resource threshold is reached. No publicly available exploits are known.

Processing time of drive search expressions now gets monitored, and the related request is terminated if a resource threshold is reached. Availability of OX App Suite could be reduced due to high processing load. Please deploy the provided updates and patch releases. Processing of user-defined drive search expressions is not limited No publicly available exploits are known.

Processing of user-defined DAV user-agent strings is not limited. Availability of OX App Suite could be reduced due to high processing load. Please deploy the provided updates and patch releases. Processing time of DAV user-agents now gets monitored, and the related request is terminated if a resource threshold is reached. No publicly available exploits are known.

Processing of CID references at E-Mail can be abused to inject malicious script code that passes the sanitization engine. Malicious script code could be injected to a users sessions when interacting with E-Mails. Please deploy the provided updates and patch releases. CID handing has been improved and resulting content is checked for malicious content. No publicly available exploits are known.

User ID references at mentions in document comments were not correctly sanitized. Script code could be injected to a users session when working with a malicious document. Please deploy the provided updates and patch releases. User-defined content like comments and mentions are now filtered to avoid potentially malicious content. No publicly available exploits are known.

User-defined script code could be stored for a upsell related shop URL. This code was not correctly sanitized when adding it to DOM. Attackers could lure victims to user accounts with malicious script code and make them execute it in the context of a trusted domain. We added sanitization for this content. No publicly available exploits are known.

Users were able to define disclaimer texts for an upsell shop dialog that would contain script code that was not sanitized correctly. Attackers could lure victims to user accounts with malicious script code and make them execute it in the context of a trusted domain. We added sanitization for this content. No publicly available exploits are known.

User-defined OXMF templates could be used to access a limited part of the internal OX App Suite Java API. The existing switch to disable the feature by default was not effective in this case. Unauthorized users could discover and modify application state, including objects related to other users and contexts. We now make sure that the switch to disable user-generated templates by default works as intended and will remove the feature in future generations of the product. No publicly available exploits are known.

The optional "LDAP contacts provider" could be abused by privileged users to inject LDAP filter strings that allow to access content outside of the intended hierarchy. Unauthorized users could break confidentiality of information in the directory and potentially cause high load on the directory server, leading to denial of service. Encoding has been added for user-provided fragments that are used when constructing the LDAP query. No publicly available exploits are known.

The "upsell" widget at the portal page could be abused to inject arbitrary script code. Attackers that manage to lure users to a compromised account, or gain temporary access to a legitimate account, could inject script code to gain persistent code execution capabilities under a trusted domain. User input for this widget is now sanitized to avoid malicious content the be processed. No publicly available exploits are known.

A component for parsing OXMF templates could be abused to execute arbitrary system commands that would be executed as the non-privileged runtime user. Users and attackers could run system commands with limited privilege to gain unauthorized access to confidential information and potentially violate integrity by modifying resources. The template engine has been reconfigured to deny execution of harmful commands on a system level. No publicly available exploits are known.