Cisco Security Advisory
Cisco IOS XE Software Privilege Escalation Vulnerabilities
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CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:X/RL:X/RC:X
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Multiple vulnerabilities in the web management framework of Cisco IOS XE Software could allow an authenticated, remote attacker with read-only privileges to elevate privileges to the level of an Administrator user on an affected device.
For more information about these vulnerabilities, see the Details section of this advisory.
Cisco has released software updates that address these vulnerabilities. There are no workarounds that address these vulnerabilities.
This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-webui-priv-esc-K8zvEWMThis advisory is part of the September 24, 2020, release of the Cisco IOS and IOS XE Software Security Advisory Bundled Publication, which includes 25 Cisco Security Advisories that describe 34 vulnerabilities. For a complete list of the advisories and links to them, see Cisco Event Response: September 2020 Semiannual Cisco IOS and IOS XE Software Security Advisory Bundled Publication.
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Vulnerable Products
These vulnerabilities affect Cisco devices if they are running a vulnerable release of Cisco IOS XE Software and have the HTTP server enabled. The default state of the HTTP Server feature in Cisco IOS XE Software is version dependent.
For information about which Cisco software releases are vulnerable, see the Fixed Software section of this advisory.
Determine the HTTP Server Configuration
To determine whether the HTTP Server feature is enabled for a device, log in to the device and use the show running-config | include ip http server|secure|active command in the CLI to check for the presence of the ip http server command or the ip http secure-server command in the global configuration. If either command is present and configured, the HTTP Server feature is enabled for the device.
The following example shows the output of the show running-config | include ip http server|secure|active command for a device that has the HTTP Server feature enabled:
Router# show running-config | include ip http server|secure|active
ip http server
ip http secure-serverNote: The presence of either command or both commands in the device configuration indicates that the web UI feature is enabled.
If the ip http server command is present and the configuration also contains ip http active-session-modules none, the vulnerabilities are not exploitable over HTTP.
If the ip http secure-server command is present and the configuration also contains ip http secure-active-session-modules none, the vulnerabilities are not exploitable over HTTPS.
Products Confirmed Not Vulnerable
Only products listed in the Vulnerable Products section of this advisory are known to be affected by these vulnerabilities.
Cisco has confirmed that these vulnerabilities do not affect the following Cisco products:
- IOS Software
- IOS XR Software
- NX-OS Software
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The vulnerabilities are not dependent on one another. Exploitation of one of the vulnerabilities is not required to exploit the other vulnerability. In addition, a software release that is affected by one of the vulnerabilities may not be affected by the other vulnerability.
Details about the vulnerabilities are as follows.
Cisco IOS XE Web Management Software Privilege Escalation Vulnerability
A vulnerability in the APIs of the web management framework of Cisco IOS XE Software could allow an authenticated, remote attacker with read-only privileges to elevate privileges to the level of an Administrator user on an affected device.
The vulnerability is due to a lack of input and validation checking mechanisms for certain HTTP requests to APIs on an affected device. An attacker could exploit this vulnerability by sending a modified HTTP request to the affected device. An exploit could allow the attacker as a read-only user to execute CLI commands or configuration changes as if they were an administrative user.
Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.
Bug ID(s): CSCvu90974
CVE ID: CVE-2020-3141
Security Impact Rating (SIR): High
CVSS Base Score: 8.8
CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HCisco IOS XE Web Management Software Privilege Escalation Vulnerability
A vulnerability in the authentication controls of the web management framework of Cisco IOS XE Software could allow an authenticated, remote attacker with read-only privileges to elevate privileges to the level of an Administrator user on an affected device.
The vulnerability is due to insufficient data protection of sensitive information. An attacker with read-only privileges could exploit this vulnerability by sending a crafted API call. A successful exploit could allow the attacker to obtain a privileged authentication token, which the attacker could use to elevate their privileges to the level of an administrative user on the affected device.
Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.
Bug ID(s): CSCvs40347
CVE ID: CVE-2020-3425
Security Impact Rating (SIR): High
CVSS Base Score: 8.8
CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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There are no workarounds that address these vulnerabilities.
Disabling the HTTP Server feature eliminates the attack vector for these vulnerabilities and may be a suitable mitigation until affected devices can be upgraded. To disable the HTTP Server feature, use the no ip http server or no ip http secure-server command in global configuration mode. If both the HTTP server and HTTPS server are in use, both commands are required to disable the HTTP Server feature.
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Cisco has released free software updates that address the vulnerabilities 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.htmlAdditionally, 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.
Cisco IOS and IOS XE Software
To help customers determine their exposure to vulnerabilities in Cisco IOS and IOS XE Software, Cisco provides the Cisco Software Checker to identify any Cisco Security Advisories that impact a specific software release and the earliest release that fixes the vulnerabilities described in each advisory (“First Fixed”). If applicable, the tool also returns the earliest release that fixes all the vulnerabilities described in all the advisories identified (“Combined First Fixed”).
Customers can use the Cisco Software Checker to search advisories in the following ways:
- Choose the software and one or more releases
- Upload a .txt file that includes a list of specific releases
- Enter the output of the show version command
After initiating a search, customers can customize the search to include all Cisco Security Advisories, a specific advisory, or all advisories in the most recent bundled publication.
Customers can also use the following form to determine whether a release is affected by any Cisco Security Advisory by entering a Cisco IOS or IOS XE Software release-for example, 15.1(4)M2 or 3.13.8S:
By default, the Cisco Software Checker includes results only for vulnerabilities that have a Critical or High Security Impact Rating (SIR). To include results for Medium SIR vulnerabilities, customers can use the Cisco Software Checker on Cisco.com and check the Medium check box in the drop-down list under Impact Rating when customizing a search.
For a mapping of Cisco IOS XE Software releases to Cisco IOS Software releases, refer to the Cisco IOS XE 2 Release Notes, Cisco IOS XE 3S Release Notes, or Cisco IOS XE 3SG Release Notes, depending on the Cisco IOS XE Software release.
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The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerabilities that are described in this advisory.
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Cisco would like to thank Kwangho Park (panghoddari) of KITRI BoB for finding and reporting the vulnerability identified as CVE-2020-3425.
The vulnerability identified as CVE-2020-3141 was found during internal security testing by P.W. of the Cisco Advanced Security Initiatives Group (ASIG).
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To learn about Cisco security vulnerability disclosure policies and publications, see the Security Vulnerability Policy. This document also contains instructions for obtaining fixed software and receiving security vulnerability information from Cisco.
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Show LessVersion Description Section Status Date 1.0 Initial public release. - Final 2020-SEP-24
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