==================================================================== CERT-Renater Note d'Information No. 2020/VULN490 _____________________________________________________________________ DATE : 03/09/2020 HARDWARE PLATFORM(S): / OPERATING SYSTEM(S): Cisco IOS XR versions prior to 6.6.3, 7.0.2, 7.1.1, SMU ID for 6.5.29 - AA17787. ===================================================================== https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-cli-privescl-sDVEmhqv https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-LJtNFjeN _____________________________________________________________________ Cisco IOS XR Authenticated User Privilege Escalation Vulnerability High Advisory ID: cisco-sa-iosxr-cli-privescl-sDVEmhqv First Published: 2020 September 2 16:00 GMT Version 1.0: Final Workarounds: Yes Cisco Bug IDs: CSCvu79978 CSCvu99038 CSCvv05925 CVSS Score: Base 8.4 CVE-2020-3530 CWE-264 Summary A vulnerability in task group assignment for a specific CLI command in Cisco IOS XR Software could allow an authenticated, local attacker to execute that command, even though administrative privileges should be required. The attacker must have valid credentials on the affected device. The vulnerability is due to incorrect mapping in the source code of task group assignments for a specific command. An attacker could exploit this vulnerability by issuing the command, which they should not be authorized to issue, on an affected device. A successful exploit could allow the attacker to invalidate the integrity of the disk and cause the device to restart. This vulnerability could allow a user with read permissions to issue a specific command that should require Administrator privileges. Cisco has released software updates that address this vulnerability. There are workarounds that address this vulnerability. This advisory is available at the following link: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-cli-privescl-sDVEmhqv Affected Products Vulnerable Products This vulnerability affects the following Cisco products if they are running a vulnerable release of Cisco IOS XR Software: ASR 9000 Series Aggregation Services Routers (32-bit and 64-bit models) IOS XR, SW only Network Convergence System 1000 Series Network Convergence System 5000 Series Network Convergence System 5500 Series For information about which Cisco software releases are vulnerable, see the Fixed Software section of this advisory. Products Confirmed Not Vulnerable Only products listed in the Vulnerable Products section of this advisory are known to be affected by this vulnerability. Cisco has confirmed that this vulnerability does not affect the following Cisco products: 8000 Series Routers Carrier Routing System IOS XRv 9000 Routers Network Convergence System 520 Routers Network Convergence System 540 Series Routers Network Convergence System 560 Series Routers Network Convergence System 4000 Series Network Convergence System 4200 Series Network Convergence System 6000 Series Routers Workarounds Workarounds exist only for devices that have TACACS+ authentication, authorization, and accounting (AAA) command authorization configured. Administrators can use this feature to give nonadministrative users access to the commands that they require and deny access to all other commands. For more information about Cisco IOS XR task groups and AAA, see ASR9000/XR Using Task groups and understanding Priv levels and authorization. Fixed Software Cisco has released free software updates that address the vulnerability described in this advisory. Customers may only install and expect support for software versions and feature sets for which they have purchased a license. By installing, downloading, accessing, or otherwise using such software upgrades, customers agree to follow the terms of the Cisco software license: https://www.cisco.com/c/en/us/products/end-user-license-agreement.html Additionally, customers may only download software for which they have a valid license, procured from Cisco directly, or through a Cisco authorized reseller or partner. In most cases this will be a maintenance upgrade to software that was previously purchased. Free security software updates do not entitle customers to a new software license, additional software feature sets, or major revision upgrades. When considering software upgrades, customers are advised to regularly consult the advisories for Cisco products, which are available from the Cisco Security Advisories page, to determine exposure and a complete upgrade solution. In all cases, customers should ensure that the devices to be upgraded contain sufficient memory and confirm that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, customers are advised to contact the Cisco Technical Assistance Center (TAC) or their contracted maintenance providers. Customers Without Service Contracts Customers who purchase directly from Cisco but do not hold a Cisco service contract and customers who make purchases through third-party vendors but are unsuccessful in obtaining fixed software through their point of sale should obtain upgrades by contacting the Cisco TAC: https://www.cisco.com/c/en/us/support/web/tsd-cisco-worldwide-contacts.html Customers should have the product serial number available and be prepared to provide the URL of this advisory as evidence of entitlement to a free upgrade. Fixed Releases Cisco has fixed this vulnerability in Cisco IOS XR releases 7.1.2 and later for the following platforms: ASR 9000 Series Aggregation Services Routers (32-bit and 64-bit models) IOS XR, SW only Network Convergence System 1000 Series Network Convergence System 5000 Series Network Convergence System 5500 Series Releases earlier than Release 7.0.1 are not vulnerable. The following software maintenance upgrades (SMUs) are also available. Customers should install the appropriate SMU as shown in the following table. Customers who require SMUs for other platforms and releases should contact their support organization. IOS XR Release Platform SMU Identifier 7.0.2 ASR9K-X64 AA17739 7.0.2 NCS5500 AA17740 Exploitation and Public Announcements The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory. Source This vulnerability was found by Christopher York of Cisco during internal security testing. URL https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-cli-privescl-sDVEmhqv Revision History Version Description Section Status Date 1.0 Initial public release. — Final 2020-SEP-02 Legal Disclaimer THIS DOCUMENT IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF THE INFORMATION ON THE DOCUMENT OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME. A standalone copy or paraphrase of the text of this document that omits the distribution URL is an uncontrolled copy and may lack important information or contain factual errors. The information in this document is intended for end users of Cisco products. _____________________________________________________________________ Cisco IOS XR Software Authenticated User Privilege Escalation Vulnerability High Advisory ID: cisco-sa-iosxr-LJtNFjeN First Published: 2020 September 2 16:00 GMT Version 1.0: Final Workarounds: Yes Cisco Bug IDs: CSCvs12604 CVSS Score: Base 7.8 CVE-2020-3473 CWE-264 Summary A vulnerability in task group assignment for a specific CLI command in Cisco IOS XR Software could allow an authenticated, local CLI shell user to elevate privileges and gain full administrative control of the device. The vulnerability is due to incorrect mapping of a command to task groups within the source code. An attacker could exploit this vulnerability by first authenticating to the local CLI shell on the device and using the CLI command to bypass the task group–based checks. A successful exploit could allow the attacker to elevate privileges and perform actions on the device without authorization checks. Cisco has released software updates that address this vulnerability. There are workarounds that address this vulnerability. This advisory is available at the following link: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-LJtNFjeN Affected Products Vulnerable Products This vulnerability affects the following Cisco products if they are running a release of Cisco IOS XR Software Release 5.0.0 or later that is earlier than the first fixed release: 8000 Series Routers IOS XRv 9000 Router IOS XR, SW only Network Convergence System 540 Routers Network Convergence System 560 Routers Network Convergence System 4000 Series Network Convergence System 5500 Series Network Convergence System 6000 Series Routers Products Confirmed Not Vulnerable Only products listed in the Vulnerable Products section of this advisory are known to be affected by this vulnerability. Cisco has confirmed that this vulnerability does not affect the following Cisco products: ASR 9000 Series Aggregation Services Routers (32-bit and 64-bit models) Carrier Routing System Network Convergence System 520 Routers Network Convergence System 1000 Series Network Convergence System 4200 Series Network Convergence System 5000 Series Workarounds Workarounds exist only for devices that have TACACS+ authentication, authorization, and accounting (AAA) command authorization configured. Administrators can use this feature to permit access to only the commands that nonadministrative users require and deny access to all other commands. For more information about Cisco IOS XR task groups and AAA, see ASR9000/XR Using Task groups and understanding Priv levels and authorization. Fixed Software Cisco has released free software updates that address the vulnerability described in this advisory. Customers may only install and expect support for software versions and feature sets for which they have purchased a license. By installing, downloading, accessing, or otherwise using such software upgrades, customers agree to follow the terms of the Cisco software license: https://www.cisco.com/c/en/us/products/end-user-license-agreement.html Additionally, customers may only download software for which they have a valid license, procured from Cisco directly, or through a Cisco authorized reseller or partner. In most cases this will be a maintenance upgrade to software that was previously purchased. Free security software updates do not entitle customers to a new software license, additional software feature sets, or major revision upgrades. When considering software upgrades, customers are advised to regularly consult the advisories for Cisco products, which are available from the Cisco Security Advisories page, to determine exposure and a complete upgrade solution. In all cases, customers should ensure that the devices to be upgraded contain sufficient memory and confirm that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, customers are advised to contact the Cisco Technical Assistance Center (TAC) or their contracted maintenance providers. Customers Without Service Contracts Customers who purchase directly from Cisco but do not hold a Cisco service contract and customers who make purchases through third-party vendors but are unsuccessful in obtaining fixed software through their point of sale should obtain upgrades by contacting the Cisco TAC: https://www.cisco.com/c/en/us/support/web/tsd-cisco-worldwide-contacts.html Customers should have the product serial number available and be prepared to provide the URL of this advisory as evidence of entitlement to a free upgrade. Fixed Releases Customers are advised to upgrade to an appropriate fixed software release as indicated in the following table: Cisco Platform First Fixed Releases 8000 Series Routers 7.0.12, 7.2.1, and later IOS XRv 9000 Router 6.6.3, 7.0.2, 7.1.1, and later IOS XR, SW only 7.0.2, 7.1.1, and later Network Convergence System 540 Routers 6.6.3, 7.0.2, 7.1.1, and later Network Convergence System 560 Routers 6.6.3, 7.0.2, 7.1.1, and later Network Convergence System 4000 Series SMU ID for 6.5.29 - AA17787 Network Convergence System 5500 Series 6.6.3, 7.0.2, 7.1.1, and later Network Convergence System 6000 Series Routers 6.6.3, 7.0.2, 7.1.1, and later Exploitation and Public Announcements The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory. Source This vulnerability was found during internal security testing. URL https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-LJtNFjeN Revision History Version Description Section Status Date 1.0 Initial public release. — Final 2020-SEP-02 Legal Disclaimer THIS DOCUMENT IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. YOUR USE OF THE INFORMATION ON THE DOCUMENT OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME. A standalone copy or paraphrase of the text of this document that omits the distribution URL is an uncontrolled copy and may lack important information or contain factual errors. The information in this document is intended for end users of Cisco products. ========================================================= + CERT-RENATER       |    tel : 01-53-94-20-44          + + 23/25 Rue Daviel   |    fax : 01-53-94-20-41          + + 75013 Paris        |    email:cert@support.renater.fr + =========================================================