Security Advisories

A potential for information disclosure was identified in a packaged library, HTML TreeBuilder.

CiviCRM now patches the TreeBuilder library to direct debug output to the CiviCRM debug log, rather than to screen.

This release addresses an issue where it was possible to deliver a cross-site scripting attack through the CiviCRM backend.

To exploit this vulnerability, both the attacker and victim need permission to access the CiviCRM backend, and the victim must visit a specific screen.

For more information about this type of vulnerability, see OWASP's page on Cross Site Scripting.

Multiple SQL injections have been identified in AJAX helpers supporting backend forms. An exploit has been demonstrated. Executing an exploit requires a user account with some kind of CiviCRM permission (such as "access CiviCRM" or "view my contact").

A bundled library, TCPDF, had a recent security flaw patched. This vulnerability permitted a malicious user to make the PDF library perform unexpected actions, potentially permitting data disclosure. This was mitigated by the fact that only administrative users have access to the PDF generation functionality which uses TCPDF.

In some configurations, a malicious backend user may be able to impersonate another backend user. Some conditions must be met to be exploitable:

• The malicious backend user must already have write-access to the target user's contact record.
• The malicious backend user must know the CIVICRM_SITE_KEY.

The CiviCRM installer was potentially vulnerable to SQL injection.

The 4.6.11 release of CiviCRM addresses multiple vulnerabilities in DOMPDF, a library used within CiviCRM to generate PDFs.

For more information, see the DOMPDF release notes for DOMPDF v0.6.2

The 4.6.11 release of CiviCRM addresses an issue whereby users with limited administrative rights (data viewing) were able to modify certain fields within CiviCRM.

The 4.6.11 release of CiviCRM addresses an issue whereby directly accessing certain CiviCRM files could reveal the full path of the active CiviCRM installation.

This is Full Path Disclosure and while not directly exploitable, in combination with other attacks it may weaken the security of an installation.

For more information on this type of vulnerability, see OWASP's page on Full Path Disclosure.

The CiviCRM footer may have been displayed to users without "access CiviCRM" permission under certain conditions. The footer shows limited version information and upgrade notifications, which could be used by an attacker to identify vulnerabilities based on whether the installed version is up-to-date.

There was a bug in one of CiviCRM's internal type checks which may allow inappropriate user input to be saved to the database and/or displayed.

This was a general weakness in one of CiviCRM's security layers; no specific exploits of this have been identified. This type of vulnerability could potentially allow attackers to save malicious content to the database or display it to site users.

CiviCRM 4.6.7 introduced an access bypass issue which applied a limited number of sites.

The issue affected only certain configurations, where the site used ACLs to limit access, and applied to users whose permissions included “access CiviCRM” and “view my contact” but not “view all contacts”. Changes introduced in CRM-16512 allowed the “view my contact” permission for those users to incorrectly grant access to all contacts.

The contribution page's return URL could be used to redirect site visitors to another URL.

For more information about this type of attack, see OWASP's reference page on open redirects.

This release addresses an issue where it was possible to deliver XSS by directing a user to a CiviCRM URL which triggered a fatal error. The issue has been addressed by correctly escaping output from CiviCRM's fatal error handler.

For more information about this type of vulnerability, see OWASP's page on Cross Site Scripting.

The backend CiviMail composition screen includes an input field which is passed to a SQL query without proper escaping.

An exploit of this vulnerability in CiviCRM has not been identified. Additional filters apply to the field which block a number of SQL control characters. Never-the-less, it could potentially be combined with other vulnerabilities, and we're issuing a patch as a precaution.

The Smarty templating engine includes a defect in which a specially named Smarty template could be used to execute PHP code.

An exploit of this vulnerability in CiviCRM has not been identified. Exploiting it requires that an attacker have permission to set the name and content of a template file; in CiviCRM deployments, this permission is generally only available to system administrators. Never-the-less, it could potentially be combined with other vulnerabilities, and we're issuing a patch as a precaution.

By default, CiviCRM records log entries in a flat text file. Optionally, log entries may be directed to Drupal's watchdog() service. If this option is enabled, and if a log entry includes user-supplied data, the user-supplied data may not be correctly encoded. When an administrator browses the log entries, they may be exposed to a cross-site scripting attack.

Cross-Site Scripting (XSS) is a technique used to embed malicious content into the resulting web page. As such, it is pertinent to note that this class of attack targets end-users rather than the web application itself. When this attack is considered “reflected”, a user requests a web page with a payload which is embedded within a crafted hyperlink or a malicious page.

Certain AJAX callbacks in CiviCRM did not properly encode their outputs - making them vulnerable to cross-site scripting attacks.

CiviCRM includes the dompdf library for generating PDF documents. The dompdf library includes a standalone utility script, "dompdf.php"; old versions of the script are vulnerable to an arbitrary file access issue when the system is configured with option "DOMPDF_ENABLE_REMOTE".

CiviCase functionality includes several urls which allow a user to view and edit a limited amount of case info. Some of these urls were not adequately checking permissions and could be used by any user with "Access CiviCRM" permission.

This problem only affects sites using the CiviCase component. It is mitigated by the fact that the user must have "Access CiviCRM," a permission not normally granted to untrusted users.

CiviCRM Access Control Lists (ACLs) allow site administrators to grant or revoke access to specifics groups/contacts. In CiviCRM 4.4.x, any staff user with access to the "Export" functionality could bypass the ACLs.

CiviCRM uses AJAX callbacks to provide advisory details while completing certain forms. For example, when registering a new user through a profile form, CiviCRM issues an AJAX request to determine whether the username is available.

Some AJAX callbacks did not test for authorization, enabling untrusted parties to:

• Determine whether a username was in-use
• Determine the primary email address for a given contact ID
• Determine the list of available options in certain custom-field

The CiviCRM Profile subsystem allows administrators to design customized forms. The subsystem includes some advanced workflow settings which are not securely handled. By submitting a custom-crafted form to the Profile subsystem, an attacker may manipulate these settings. This vulnerability can be leveraged to acquire escalated privileges and (possibly) to issue open redirects.

A small number of CiviCRM entry points had faulty permission checks. This could allow hackers, under certain circumstances, to view basic contact information such as name, email, phone, or address for contacts in the database.

The risk is limited to viewing basic contact information - it does not include contributions, memberships, passwords or other data. It does not give hackers the ability to login or make changes to the database.

All sites are advised to upgrade immediately to avoid the potential risk.