Protect yourself against future threats.
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2016.2366 Drupal file upload by anonymous or untrusted users into public file systems -- PSA-2016-003 11 October 2016 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: Drupal Publisher: Drupal Operating System: UNIX variants (UNIX, Linux, OSX) Windows Impact/Access: Create Arbitrary Files -- Remote/Unauthenticated Resolution: Mitigation Original Bulletin: https://www.drupal.org/psa-2016-003 - --------------------------BEGIN INCLUDED TEXT-------------------- View online: https://www.drupal.org/psa-2016-003 * Advisory ID: DRUPAL-PSA-2016-003 * Project: Drupal core [1] * Version: 7.x, 8.x * Date: 2016-October-10 * Security risk: 20/25 ( Critical) AC:None/A:None/CI:Some/II:Some/E:Exploit/TD:All [2] - -------- DESCRIPTION --------------------------------------------------------- Recently the Drupal Security Team has seen a trend of attacks utilizing a site mis-configuration. This issue only affects sites that allow file uploads by non-trusted or anonymous visitors, and stores those uploads in a public file system. These files are publically accessible allowing attackers to point search engines and people directly to them on the site. The majority of the reports are based around the webform module, however, other modules are vulnerable to this misconfiguration as well. For example, if a webform configured to allow anonymous visitors to upload an image into the public file system, that image would then be accessible by anyone on the internet. The site could be used by an attacker to host images and other files that the legitimate site maintainers would not want made publicly available through their site. - -------- TO RESOLVE THIS ISSUE: ---------------------------------------------- 1) Configure upload fields that non-trusted visitors, including anonymous visitors, can upload files with, to utilize use the private file system [3]. 2) Ensure cron is properly running on the site. Read about setting up cron for for Drupal 7 [4] or or Drupal 8 [5]). 3) Consider forcing users to create accounts before submitting content. 4) Audit your public file space to make sure that files that are uploaded there are valid. - -------- AWARENESS ACKNOWLEDGMENT -------------------------------------------- The Drupal Security Team became aware of the existence and exploits of this issue because the community reported this issue to the security team [6]. As always, if your site has been exploited, even if the cause is a mistake in configuration, the security team is interested in hearing about the nature of the issue. We use these reports to look for trends and broader solutions. - -------- COORDINATED BY ------------------------------------------------------ * Michael Hess [7] of the Drupal Security Team * Damien McKenna [8] of the Drupal Security Team * Alex Pott [9] of the Drupal Security Team * David Snopek [10] of the Drupal Security Team * Greg Knaddison [11] of the Drupal Security Team * Cash Williams [12] of the Drupal Security Team *This post may be updated as more information is learned.* - -------- CONTACT AND MORE INFORMATION ---------------------------------------- The Drupal security team can be reached at security at drupal.org or via the contact form at https://www.drupal.org/contact [13]. Learn more about the Drupal Security team and their policies [14], writing secure code for Drupal [15], and securing your site [16]. [1] https://www.drupal.org/project/drupal [2] https://www.drupal.org/security-team/risk-levels [3] https://www.drupal.org/documentation/modules/file#access [4] https://www.drupal.org/docs/7/setting-up-cron/overview [5] https://www.drupal.org/docs/8/setting-up-cron/overview [6] https://www.drupal.org//www.drupal.org/node/101494â\x{128}\x{157} [7] https://www.drupal.org/u/mlhess [8] https://www.drupal.org/u/damienmcKenna [9] https://www.drupal.org/u/alexpott [10] https://www.drupal.org/u/dsnopek [11] https://www.drupal.org/u/greggles [12] https://www.drupal.org/u/cashwilliams [13] https://www.drupal.org/contact [14] https://www.drupal.org/security-team [15] https://www.drupal.org/writing-secure-code [16] https://www.drupal.org/security/secure-configuration - --------------------------END INCLUDED TEXT-------------------- You have received this e-mail bulletin as a result of your organisation's registration with AusCERT. The mailing list you are subscribed to is maintained within your organisation, so if you do not wish to continue receiving these bulletins you should contact your local IT manager. If you do not know who that is, please send an email to auscert@auscert.org.au and we will forward your request to the appropriate person. NOTE: Third Party Rights This security bulletin is provided as a service to AusCERT's members. As AusCERT did not write the document quoted above, AusCERT has had no control over its content. The decision to follow or act on information or advice contained in this security bulletin is the responsibility of each user or organisation, and should be considered in accordance with your organisation's site policies and procedures. AusCERT takes no responsibility for consequences which may arise from following or acting on information or advice contained in this security bulletin. NOTE: This is only the original release of the security bulletin. It may not be updated when updates to the original are made. If downloading at a later date, it is recommended that the bulletin is retrieved directly from the author's website to ensure that the information is still current. Contact information for the authors of the original document is included in the Security Bulletin above. If you have any questions or need further information, please contact them directly. Previous advisories and external security bulletins can be retrieved from: http://www.auscert.org.au/render.html?cid=1980 =========================================================================== Australian Computer Emergency Response Team The University of Queensland Brisbane Qld 4072 Internet Email: auscert@auscert.org.au Facsimile: (07) 3365 7031 Telephone: (07) 3365 4417 (International: +61 7 3365 4417) AusCERT personnel answer during Queensland business hours which are GMT+10:00 (AEST). On call after hours for member emergencies only. =========================================================================== -----BEGIN PGP SIGNATURE----- Comment: http://www.auscert.org.au/render.html?it=1967 iQIVAwUBV/x1mIx+lLeg9Ub1AQjF8RAArGVukLYeP8Kd70MPlszS+tjKB5yfUR5g m+f6AeBBwCdtHG0iijl0VlImQgOyNYlPEVjGVGbXkex/SotxqhihdDFUDT2aImWi HlJQpfGsiHpSyqmwaxOt2Nzcw8AgaNYYrMQuXO3N1D+kmX4lYs/LzbFEQmsEeZOm /qs84ZN92IwG1PsAoKQLKgmaBmVRS/YCJ7UbIgO8ocyGSKCt2DnH7/P+sNdqWKDN nK6FgGmplXnicX9+/ydfy8oCJrcM2YRMuULgxspjtmVl6M+93Ng8pQMBE7KB6uZp XqKE57jhwzDFdEgxnwXE2mxfx+gSt5PJj99GaI4Oe8EJkhUMNugwsYzk4LOA/r+c StU0gqRk9EMZ0/34nRl6UpCZazRVUI1NLpr7CfxICsMcjNaeIDpFdkXM9VTTGBHp A4X8DAyG5KDLqS7FPrZ1cbkW2REUu79/iFCgy6zFjj8jW7fPJZF7YVlcJlKuyblB h4yNrEKfxRtknG4H/+vDDubD5A68X8ELU/qbOcmSFHd6NieOMJrS3NXnkrJl8k7x T+3iZPqQyzAxvXXTtQvZA4o3m6ALSruPgyYd15W1ZCzLiH+VfWCCuYpvICeWFkSi gpNah5g6rwgGNUTzGwxoT+19cv5vU8JbqHGXVBdmJVoKU/YOSlQM0n+cYxU/sqW4 1lsdctXXmyc= =gaJg -----END PGP SIGNATURE-----