search menu icon-carat-right cmu-wordmark

CERT Coordination Center

ShareLaTeX vulnerable to remote command execution and information disclosure

Vulnerability Note VU#302668

Original Release Date: 2015-03-03 | Last Revised: 2015-03-03

Overview

ShareLaTeX is a server-based software allowing group collaboration on LaTeX documents. ShareLaTeX prior to version 0.1.3 has been found to be vulnerable to command injections and information disclosure.

Description

CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') - CVE-2015-0933

ShareLaTeX 0.1.3 and previous versions allow a remote user to obtain information about other users or the server on which ShareLaTeX is installed by allowing a user to \include{} any valid absolute path name in the document, which is then forwarded to the latex process. When processed, the output document will contain the contents of the file specified.

CWE-77: Improper Neutralization of Special Elements used in a Command ('Command Injection') - CVE-2015-0934

ShareLaTeX prior to version 0.1.3 allows a remote user to run commands on the server with the permissions of the ShareLaTeX process by not properly filtering out backticks from the names of files.

The CVSS score below is based on CVE-2015-0934.

Impact

CVE-2015-0933 allows a remote authenticated user to obtain information about other users or the server on which ShareLaTeX is installed. This information can include information like user accounts, which may be used to mount further attacks against the server.

CVE-2015-0934 allows a remote authenticated user to run commands on the server with the permissions of the ShareLaTeX process.

Note that user authentication as of ShareLaTeX 0.1.3 is currently limited to registering an email address and does not require moderator/administrator approval. Therefore it is possible for an authenticated user to remain anonymous.

Solution

Apply an update

CVE-2015-0934 was addressed in CLSI 0.1.3, which is included in ShareLaTeX 0.1.3. Users are recommended to update as soon as possible. This update does not address CVE-2015-0933, however. You may consider the following workaround for CVE-2015-0933.

Change LaTeX configuration

CVE-2015-0933 may be mitigated by making some changes to the LaTeX configuration file on the server running ShareLaTeX. ShareLaTeX provides some extra security guidance.

Vendor Information

302668
 
Affected   Unknown   Unaffected

ShareLaTeX

Updated:  March 03, 2015

Status

  Affected

Vendor Statement

No statement is currently available from the vendor regarding this vulnerability.

Vendor Information

We are not aware of further vendor information regarding this vulnerability.

Vendor References

https://github.com/sharelatex/sharelatex/wiki/Production-Installation-Instructions#securing-latex https://github.com/sharelatex/sharelatex/tree/v0.1.3


CVSS Metrics

Group Score Vector
Base 6.4 AV:N/AC:L/Au:N/C:P/I:P/A:N
Temporal 5.0 E:POC/RL:OF/RC:C
Environmental 1.3 CDP:ND/TD:L/CR:ND/IR:ND/AR:ND

References

Credit

Thanks to Tobias Fiebig for reporting this vulnerability.

This document was written by Garret Wassermann.

Other Information

CVE IDs: CVE-2015-0933, CVE-2015-0934
Date Public: 2015-03-02
Date First Published: 2015-03-03
Date Last Updated: 2015-03-03 17:51 UTC
Document Revision: 44

Sponsored by the Department of Homeland Security Office of Cybersecurity and Communications.