Protect yourself against future threats.
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA256
===========================================================================
AUSCERT External Security Bulletin Redistribution
ESB-2020.4104.2
Cisco Expressway Software Unauthorized Access Information
Disclosure Vulnerability
21 January 2021
===========================================================================
AusCERT Security Bulletin Summary
---------------------------------
Product: Cisco Expressway Software
Publisher: Cisco Systems
Operating System: Cisco
Impact/Access: Unauthorised Access -- Remote/Unauthenticated
Resolution: Patch/Upgrade
CVE Names: CVE-2020-3482
Original Bulletin:
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-Expressway-8J3yZ7hV
Revision History: January 21 2021: Vendor downgraded rating from medium to informationation
November 19 2020: Initial Release
- --------------------------BEGIN INCLUDED TEXT--------------------
Cisco Expressway Software TURN Server Configuration Issue
Priority: Informational
Advisory ID: cisco-sa-Expressway-8J3yZ7hV
First Published: 2020 November 18 16:00 GMT
Last Updated: 2021 January 20 20:41 GMT
Version 2.0: Final
Workarounds: No workarounds available
Cisco Bug IDs: CSCvt83751
CVE Names: CVE-2020-3482
CWEs: CWE-284
Summary
o The Traversal Using Relays around NAT (TURN) server component of Cisco
Expressway software supports the relay of media connections through a
firewall using proxy services. As a result of this feature, interfaces such
as the Cisco Expressway web administrative interface may become accessible
from external networks.
At the time of publication, documentation of the feature did not properly
explain that users are able to bypass firewall protections that are
designed to restrict access to the Cisco Expressway web administrative
interface. However, an attacker must have credentials sufficient to use
TURN services to be able to send network requests to the web administrative
interface.
This advisory is available at the following link:
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-Expressway-8J3yZ7hV
Affected Products
o Vulnerable Products
This issue impacts Cisco Expressway Series and Cisco TelePresence Video
Communication Server (VCS) with the TURN server feature enabled.
Products Confirmed Not Vulnerable
Only products listed in the Vulnerable Products section of this advisory
are known to be affected.
Cisco has confirmed that Cisco Expressway Series and Cisco TelePresence VCS
systems that do not have the TURN server feature enabled are not affected.
Details
o The Cisco Expressway IP Port Usage Configuration Guide recommends firewall
configuration to prevent access to administrative ports from external
networks. However, when TURN services are enabled, administrative ports are
accessible through the TURN server from external networks. Customers should
be aware that enabling the TURN services exposes administrative ports on
the Cisco Expressway Series or Cisco TelePresence VCS host.
Workarounds
o There are no workarounds that address this issue.
Exploitation and Public Announcements
o The Cisco Product Security Incident Response Team (PSIRT) is not aware of
any public announcements or malicious use of the issue that is described in
this advisory.
Source
o Cisco would like to thank Christian Mehlmauer of WienCERT-IT-Security in
the City of Vienna for reporting this issue.
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.
URL
o https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-Expressway-8J3yZ7hV
Revision History
o +---------+--------------------------+-------------+--------+-------------+
| Version | Description | Section | Status | Date |
+---------+--------------------------+-------------+--------+-------------+
| | Changed the advisory SIR | | | |
| | from Medium to | Summary, | | |
| | Informational. Updated | Vulnerable | | |
| 2.0 | throughout to explain | Products, | Final | 2021-JAN-20 |
| | that this not a | Details, | | |
| | vulnerability. Removed | and Fixed | | |
| | the Fixed Software | Software | | |
| | section. | | | |
+---------+--------------------------+-------------+--------+-------------+
| | Included additional | | | |
| 1.1 | information about the | Affected | Final | 2020-NOV-25 |
| | vulnerable | Products | | |
| | configuration. | | | |
+---------+--------------------------+-------------+--------+-------------+
| 1.0 | Initial public release. | - | Final | 2020-NOV-18 |
+---------+--------------------------+-------------+--------+-------------+
- --------------------------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: http://www.auscert.org.au/render.html?it=1967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=kXek
-----END PGP SIGNATURE-----