Protect yourself against future threats.
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 =========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2022.3979.4 Cisco Adaptive Security Appliance Software Clientless SSL VPN Client-Side Request Smuggling Vulnerability 22 December 2022 =========================================================================== AusCERT Security Bulletin Summary --------------------------------- Product: Cisco Adaptive Security Appliance Software Publisher: Cisco Systems Operating System: Cisco Resolution: Mitigation CVE Names: CVE-2022-20713 Original Bulletin: https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-webvpn-LOeKsNmO Comment: CVSS (Max): 4.3 CVE-2022-20713 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N) CVSS Source: Cisco Systems Calculator: https://www.first.org/cvss/calculator/3.1#CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N Revision History: December 22 2022: Updated information about fixed software availability November 11 2022: Updated Subject to include CVSS Score November 10 2022: Vendor updated bulletin August 11 2022: Initial Release - --------------------------BEGIN INCLUDED TEXT-------------------- Cisco Adaptive Security Appliance and Firepower Threat Defense Software VPN Web Client Services Client-Side Request Smuggling Vulnerability Priority: Medium Advisory ID: cisco-sa-asa-webvpn-LOeKsNmO First Published: 2022 August 10 16:00 GMT Last Updated: 2022 December 16 18:00 GMT Version 2.1: Final Workarounds: No workarounds available Cisco Bug IDs: CSCwa04262 CVE Names: CVE-2022-20713 Summary o A vulnerability in the VPN web client services component of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to conduct browser-based attacks against users of an affected device. This vulnerability is due to improper validation of input that is passed to the VPN web client services component before being returned to the browser that is in use. An attacker could exploit this vulnerability by persuading a user to visit a website that is designed to pass malicious requests to a device that is running Cisco ASA Software or Cisco FTD Software and has web services endpoints supporting VPN features enabled. A successful exploit could allow the attacker to reflect malicious input from the affected device to the browser that is in use and conduct browser-based attacks, including cross-site scripting attacks. The attacker could not directly impact the affected device. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-webvpn-LOeKsNmO Affected Products o Vulnerable Products At the time of publication, this vulnerability affected Cisco products if they were running a vulnerable release of the following Cisco software: ASA Software with Cisco AnyConnect VPN or Clientless SSL VPN enabled FTD Software with Cisco AnyConnect VPN enabled See the Details section in the bug ID(s) at the top of this advisory for the most complete and current information. Determine the ASA Software Configuration To determine whether the software has a vulnerable feature enabled, use the show-running-config CLI command. In the following table, the left column lists the Cisco ASA Software features that are vulnerable. The right column indicates the basic configuration for each feature from the show running-config CLI command. If a device is running a vulnerable release and has one of these features enabled, it is vulnerable. Cisco ASA Feature Vulnerable Configuration AnyConnect Internet Key Exchange crypto ikev2 enable client-services port Version 2 Remote Access (with client services) webvpn AnyConnect SSL VPN enable Clientless SSL VPN webvpn enable Determine the FTD Software Configuration To determine whether the software has a vulnerable feature enabled, use the show-running-config CLI command. In the following table, the left column lists the Cisco FTD Software features that are vulnerable. The right column indicates the basic configuration for each feature from the show running-config CLI command. If a device is running a vulnerable release and has one of these features enabled, it is vulnerable. Cisco FTD Feature Vulnerable Configuration AnyConnect Internet Key Exchange crypto ikev2 enable client-services port Version 2 Remote Access (with client services) ^1,2 AnyConnect SSL VPN ^1,2 webvpn enable 1. Remote Access VPN features were introduced in Cisco FTD Software Release 6.2.2. 2. Remote Access VPN features are enabled by using Devices > VPN > Remote Access in Cisco Firepower Management Center (FMC) or by using Device > Remote Access VPN in Cisco Firepower Device Manager (FDM). 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 devices with remote access VPN services that are configured to accept only AnyConnect Internet Key Exchange Version 2 Remote Access VPN with client services disabled are not affected by this vulnerability. Workarounds o There are no workarounds that address this vulnerability. Fixed Software o 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. Cisco ASA, FMC, and FTD Software To help customers determine their exposure to vulnerabilities in Cisco ASA, FMC, and FTD Software, Cisco provides the Cisco Software Checker . This tool identifies any Cisco security advisories that impact a specific software release and the earliest release that fixes the vulnerabilities that are described in each advisory ("First Fixed"). If applicable, the tool also returns the earliest release that fixes all the vulnerabilities that are described in all the advisories that the Software Checker identifies ("Combined First Fixed"). To use the tool, go to the Cisco Software Checker page and follow the instructions. Alternatively, use the following form to search for vulnerabilities that affect a specific software release. To use the form, follow these steps: 1. Choose which advisories the tool will search-all advisories, only advisories with a Critical or High Security Impact Rating (SIR) , or only this advisory. 2. Choose the appropriate software. 3. Choose the appropriate platform. 4. Enter a release number-for example, 9.16.2.11 for Cisco ASA Software or 6.6.7 for Cisco FTD Software. 5. Click Check . [2 ] [ ] [Critical,High,Medium] [Only this advisory ] [Cisco ASA Software] [Any Platform ] [ ] [Check] Exploitation and Public Announcements o The Cisco Product Security Incident Response Team (PSIRT) is aware that proof-of-concept exploit code is available for the vulnerability described in this advisory. The Cisco PSIRT is not aware of any malicious use of the vulnerability that is described in this advisory. Source o Cisco would like to thank James Kettle of Portswigger.net for reporting this vulnerability. Cisco Security Vulnerability Policy o 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. Subscribe to Cisco Security Notifications o Subscribe Related to This Advisory o URL o https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-webvpn-LOeKsNmO Revision History o +---------+-----------------------+----------------+--------+-------------+ | Version | Description | Section | Status | Date | +---------+-----------------------+----------------+--------+-------------+ | | Updated information | Summary, Fixed | | | | 2.1 | about fixed software | Software | Final | 2022-DEC-16 | | | availability. | | | | +---------+-----------------------+----------------+--------+-------------+ | | Added FTD Software as | Title, | | | | | an affected product. | Summary, | | | | | Updated the affected | Vulnerable | | | | | VPN component. | Products, | | | | 2.0 | Clarified affected | Products | Final | 2022-NOV-09 | | | software | Confirmed Not | | | | | configurations. | Vulnerable, | | | | | Removed the | and | | | | | mitigation because it | Workarounds | | | | | no longer applies. | | | | +---------+-----------------------+----------------+--------+-------------+ | 1.0 | Initial public | - | Final | 2022-AUG-10 | | | release. | | | | +---------+-----------------------+----------------+--------+-------------+ Legal Disclaimer o 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. - --------------------------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: https://www.auscert.org.au/bulletins/ =========================================================================== 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: https://auscert.org.au/gpg-key/ iQIVAwUBY6O6U8kNZI30y1K9AQhTNxAAiqpa6wKcCIoOhhXAzxOsEOeB5et3jT8A a1dRQosPRDU/cG8xpQocQg3ZBIayvRmNaI2DCN7jVD1mww+Jk38VuaL3Cdumofhm oGqD9LlrItIA6ifWtOaDFFOVZh3APXv6VmZfoHxiCJ3HPFLUjlDls4Xn/vc+UPsK clB7fxVwsSyfOXg/iUHX6PDuizAuyT01AxgQQmws2Klr822E73F05QEJFNgGr96y cGaU9XSHUng01WAaP6nOC71b1qp8966FrAl/cFZwzQsDkKXiPXGG28S4JmQMRDGj SMQw30VzueEBDT0wbTUtP3MKXQZWGBHWFfqDdcY0PrDQGmO17++FLA0JLhlM+mwg B1nkJe2Otf/NF0wfbxzdCi5e5AFUmXYk3mo5rCoTuoiPxm0/SS6e6WcnDq0P5NL9 tH180iGm0WbTvSqR+RSLVhG9ybwvVg7fUM1hJpmLzIkpHnDSG5O8qAbWpTIvqSK+ xWQNj6L3S7fxuKJgasPoZMfyjkjwbDRYfvRE54r6JUbdQ8gPOfCwWCOvmqeJHcSc LJPU94PlE3HVrU5FJgUnzCxuITDm2ixdUf1hYm7OWVlbMuWMlamtaPxvMz5kWgKb Tq8jyf941ErQJ9sGy1nQ+isCIOumUnuW8PIFwu7VGIKQjOWQ0AbbE3vjxLwELVzS ysTkz/Kpb70= =y3xl -----END PGP SIGNATURE-----