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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2016.1200 sol23073482: Nginx vulnerabilities CVE-2016-0742, CVE-2016-0746, and CVE-2016-0747 13 May 2016 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: F5 BIG-IQ products Publisher: F5 Networks Operating System: Network Appliance Impact/Access: Denial of Service -- Remote/Unauthenticated Reduced Security -- Remote/Unauthenticated Resolution: Patch/Upgrade CVE Names: CVE-2016-0747 CVE-2016-0746 CVE-2016-0742 Reference: ESB-2016.0350 Original Bulletin: https://support.f5.com/kb/en-us/solutions/public/k/23/sol23073482.html - --------------------------BEGIN INCLUDED TEXT-------------------- sol23073482: Nginx vulnerabilities CVE-2016-0742, CVE-2016-0746, and CVE-2016-0747 Security Advisory Original Publication Date: 05/11/2016 Vulnerability Description CVE-2016-0742 The resolver in nginx before 1.8.1 and 1.9.x before 1.9.10 allows remote attackers to cause a denial of service (invalid pointer dereference and worker process crash) via a crafted UDP DNS response. CVE-2016-0746 Use-after-free vulnerability in the resolver in nginx before 1.8.1 and 1.9.x before 1.9.10 allows remote attackers to cause a denial of service (worker process crash) or possibly have unspecified other impact via a crafted DNS response related to CNAME response processing. CVE-2016-0747 The resolver in nginx before 1.8.1 and 1.9.x before 1.9.10 does not properly limit CNAME resolution, which allows remote attackers to cause a denial of service (worker process resource consumption) via vectors related to arbitrary name resolution. Impact An attacker can exploit these vulnerabilities to crash the worker process or to cause an excessive resource consumption in the worker processes. On the BIG-IQ system, the default configuration of nginx or webd does not use the server interface to do outbound SSL connections. Security Issue Status F5 Product Development has assigned ID 588359 (BIG-IQ) to this vulnerability, and has evaluated the currently supported releases for potential vulnerability. To determine if your release is known to be vulnerable, the components or features that are affected by the vulnerability, and for information about releases or hotfixes that address the vulnerability, refer to the following table: Product Versions known to Versions known to be Severity Vulnerable component or feature be vulnerable not vulnerable BIG-IQ Cloud 4.3.0 - 4.5.0 4.0.0 - 4.2.0 Low Nginx# BIG-IQ Device 4.3.0 - 4.5.0 4.2.0 Low Nginx# BIG-IQ Security 4.3.0 - 4.5.0 4.0.0 - 4.2.0 Low Nginx# BIG-IQ ADC 4.5.0 None Low Nginx# BIG-IQ Centralized Management 4.6.0 None Low Nginx# BIG-IQ Cloud and Orchestration 1.0.0 None Low Nginx# #The Nginx RPM package name is rebranded as webd beginning from BIG-IQ 4.4.0, BIG-IQ Centralized Management 4.6.0, and BIG-IQ Cloud and Orchestration 1.0.0. Vulnerability Recommended Actions If you are running a version listed in the Versions known to be vulnerable column, you can eliminate this vulnerability by upgrading to a version listed in the Versions known to be not vulnerable column. If the table lists only an older version than what you are currently running, or does not list a non-vulnerable version, then no upgrade candidate currently exists. F5 responds to vulnerabilities in accordance with the Severity values published in the previous table. The Severity values and other security vulnerability parameters are defined in SOL4602: Overview of the F5 security vulnerability response policy. Removing the outbound reverse SSL proxy configuration in the webd or nginx configuration To mitigate this vulnerability, you can remove the outbound reverse SSL proxy configuration in the nginx or webd configuration file. To do so, perform one of the following procedures, depending on the affected BIG-IQ version: Impact of action: This procedure involves restarting webd or nginx daemon, which will cause the BIG-IQ user interface to be inaccessible. F5 recommends to perform this procedure during a scheduled maintenance window. BIG-IQ Centralized Management 4.6.0, BIG-IQ Cloud and Orchestration 1.0.0, and BIG-IQ 4.4.0 through 4.5.0 The webd configuration file is located at /etc/webd/webd.conf. To remove the outbound reverse SSL proxy configuration in the webd configuration file, perform the following procedure: Log in to the BIG-IQ system's advance shell using administrator role credentials. Stop the webd process by typing the following command: tmsh stop sys service webd Back up a copy of the webd configuration file using the following command syntax: cp -a /etc/webd/webd.conf /etc/webd/webd.conf.backup Using a text editor of your choice, modify the webd configuration file. Locate the outbound reverse SSL proxy configuration stanza that may appear similar to the following example: # Outbound http to https proxy # Used by the REST framework's HTTPD signing endpoint server { listen 127.0.0.1:80; location ~ /proxy/(.+) { resolver 8.8.8.8; proxy_pass https://$1$is_args$args; } } Remove the outbound reverse SSL proxy configuration stanza, save the changes, and exit the text editor. Start the webd process by typing the following command: tmsh start sys service webd BIG-IQ 4.3.0 The nginx configuration file is located at /etc/nginx/nginx.conf. To remove the outbound reverse SSL proxy configuration in the nginx configuration file, perform the following procedure: Log in to the BIG-IQ system's advance shell using administrator role credentials. Stop the nginx process by typing the following command: tmsh stop sys service nginx Back up a copy of the nginx configuration file using the following command syntax: cp -a /etc/webd/nginx.conf /etc/webd/nginx.conf.backup Using a text editor of your choice, modify the nginx configuration file. Locate the outbound reverse SSL proxy configuration stanza that may appear similar to the following example: # Outbound http to https proxy # Used by the REST framework's HTTPD signing endpoint server { listen 127.0.0.1:80; location ~ /proxy/(.+) { resolver 8.8.8.8; proxy_pass https://$1$is_args$args; } } Remove the outbound reverse SSL proxy configuration stanza, save the changes, and exit the text editor. Start the nginx process by typing the following command: tmsh start sys service nginx Supplemental Information SOL9970: Subscribing to email notifications regarding F5 products SOL9957: Creating a custom RSS feed to view new and updated documents SOL4602: Overview of the F5 security vulnerability response policy SOL4918: Overview of the F5 critical issue hotfix policy SOL167: Downloading software and firmware from F5 SOL15106: Managing BIG-IQ product hotfixes SOL15113: BIG-IQ hotfix matrix SOL14736: BIG-IQ daemons - --------------------------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 iQIVAwUBVzVMiX6ZAP0PgtI9AQJ6vw//R1rUsD+MbKGxV2oACLHq07Iz568amQVa 7RU2GPqnCySY+VyRJ4VckuxevRIZapuj30bSyDxgWMtsCiYxN9yRUfAG9hGwVgh1 QbUg0YCkKWo6MbX8U+tfdoLNXn8L+q/NVrosAeqWc/45ZzFfpgKFJwdovc2NAAZ9 2JGdq8I0u1A2AGixz+ZxDHIoJoSEnYwuuIKuCM3JfOmRae0CWVHvVC38PViiorwR ooPkb0Nu0lS4gBQhGcDUGfO7/S5ZGDoFIw+qswA/uTVF+UG+JsqXz6YhXJwUZnqD T+KSv5yg004qcIZEOsQk9BvFI29YU9FB71JQHojt9rb6m9wrJwc9jnyS0Gecbnyq JTiIew3y48SvkwDvTANfeDqcCI386uzjZl3i5bDFaup1ASAbGjuVLJRku/uCusU3 R0yca0CltnRINeCuTseKGL7zwMZqdvpMC0z5/lQlOj85Ouee1FDuU6hr5G5zXii+ Ms2j4hYtElVS8jxrWvHZhAacBoUseAC/yGIrPWVvjcDU4901i/C9wwms6dbpnXvD lJHj5MIxnjAu4fO7x1XGPxy43BC6B/bwmhx7WlVE1KUBdjvmNbCkXxFhTtkrB3IJ yzyhxX4EH7Ppcw1S3+4aNHiMugvSC9QQI7AAW8ND5draVL0Tq2IJwZ4ZOzlC2r+i CQco2GlR/sQ= =ZyUn -----END PGP SIGNATURE-----