[OCCAID] FW: US-CERT Technical Cyber Security Alert TA05-026A --
Multiple Denial-of-Service Vulnerabilities in Cisco IOS
James
james at towardex.com
Thu Jan 27 21:29:45 EST 2005
On Thu, Jan 27, 2005 at 04:27:24PM -0500, Tom McNeely wrote:
> Thankfully, OCCAID is not a Cisco Challenged Network[TM] ;>
Just because occaid isn't, doesnt mean people on this list aren't :)
Ed: Thanks for the notice btw!
-J (who is quite Cisco-challenged(tm) at edge bwahahha)
>
> Tom
>
> Edward A. Trdina III wrote:
>
> >Received this last night!
> >
> >Ed
> >
> >-----Original Message-----
> >From: "US-CERT Technical Alerts"<technical-alerts at us-cert.gov>
> >Sent: 1/26/05 6:00:43 PM
> >To: "technical-alerts at us-cert.gov"<technical-alerts at us-cert.gov>
> >Subject: US-CERT Technical Cyber Security Alert TA05-026A -- Multiple
> >Denial-of-Service Vulnerabilities in Cisco IOS
> >
> >-----BEGIN PGP SIGNED MESSAGE-----
> >Hash: SHA1
> >
> >
> > Technical Cyber Security Alert TA05-026A
> > Multiple Denial-of-Service Vulnerabilities in Cisco IOS
> >
> > Original release date: January 26, 2005
> > Last revised: --
> > Source: US-CERT
> >
> >Systems Affected
> >
> > * Cisco routers and switches running IOS in various configurations
> >
> >Overview
> >
> > Several denial-of-service vulnerabilities have been discovered in
> > Cisco's Internet Operating System (IOS). A remote attacker may be able
> > to cause an affected device to reload the operating system.
> >
> >I. Description
> >
> > Cisco has published three advisories describing flaws in IOS that
> > could allow a remote attacker to cause an affected device to reload.
> > Further details are available in the following vulnerability notes:
> >
> > VU#583638 - Cisco IOS contains DoS vulnerability in MPLS packet
> > processing
> >
> > The IOS implementation of Multi Protocol Label Switching (MPLS)
> > contains a vulnerability that allows malformed MPLS packets to cause
> > an affected device to reload. An unauthenticated attacker can send
> > these malformed packets on a local network segment that is connected
> > to a vulnerable device interface.
> >
> > VU#472582 - Cisco IOS IPv6 denial-of-service vulnerability
> >
> > A vulnerability in the way that IOS handles a sequence of specially
> > crafted IPv6 packets could cause an affected device to reload,
> > resulting in a denial of service. The vulnerability is exposed on both
> > physical interfaces (i.e., hardware interfaces), and logical
> > interfaces (i.e., software defined interfaces such as tunnels) that
> > are configured for IPv6.
> >
> > VU#689326 - Cisco IOS vulnerable to DoS via malformed BGP packet
> >
> > An IOS device that is enabled for Border Gateway Protocol (BGP) and
> > set up with the bgp log-neighbor-changes option is vulnerable to a
> > denial-of-service attack via a malformed BGP packet.
> >
> >II. Impact
> >
> > Although the underlying causes of these three vulnerabilities is
> > different, in each case a remote attacker could cause an affected
> > device to reload the operating system. This creates a
> > denial-of-service condition since packets are not forwarded through
> > the affected device while it is reloading. Repeated exploitation of
> > these vulnerabilites would result in a sustained denial-of-service
> > condition.
> >
> > Since devices running IOS may transit traffic for a number of other
> > networks, the secondary impacts of a denial of service may be severe.
> >
> >III. Solution
> >
> >Upgrade to a fixed version of IOS
> >
> > Cisco has updated versions of its IOS software to address these
> > vulnerabilities. Please refer to the "Software Versions and Fixes"
> > sections of the Cisco Security Advisories listed in Appendix A for
> > more information on upgrading.
> >
> >Workaround
> >
> > Cisco has also published practical workarounds for VU#689326 and
> > VU#583638. Please refer to the "Workarounds" section of each Cisco
> > Security Advisory listed in Appendix A for more information.
> >
> > Sites that are unable to install an upgraded version of IOS are
> > encouraged to implement these workarounds.
> >
> >Appendix A. References
> >
> > * Cisco Security Advisory: Crafted Packet Causes Reload on Cisco
> > Routers -
> > <http://www.cisco.com/warp/public/707/cisco-sa-20050126-les.shtml>
> > * Cisco Security Advisory: Multiple Crafted IPv6 Packets Cause
> > Reload -
> > <http://www.cisco.com/warp/public/707/cisco-sa-20050126-ipv6.shtml>
> > * Cisco Security Advisory: Cisco IOS Malformed BGP Packet Causes
> > Reload -
> > <http://www.cisco.com/warp/public/707/cisco-sa-20050126-bgp.shtml>
> > * US-CERT Vulnerability Note VU#583638 -
> > <http://www.kb.cert.org/vuls/id/583638>
> > * US-CERT Vulnerability Note VU#472582 -
> > <http://www.kb.cert.org/vuls/id/472582>
> > * US-CERT Vulnerability Note VU#689326 -
> > <http://www.kb.cert.org/vuls/id/689326>
> > _________________________________________________________________
> >
> > Feedback can be directed to the authors: Will Dormann, Chad Dougherty,
> > and Damon Morda
> > _________________________________________________________________
> >
> > This document is available from:
> > <http://www.us-cert.gov/cas/techalerts/TA05-026A.html>
> > _________________________________________________________________
> >
> > Copyright 2005 Carnegie Mellon University.
> > Terms of use: <http://www.us-cert.gov/legal.html>
> > _________________________________________________________________
> >
> > Revision History
> >
> > January 26, 2005: Initial release
> >
> >
> > Last updated January 26, 2005
> >
> >-----BEGIN PGP SIGNATURE-----
> >Version: GnuPG v1.2.1 (GNU/Linux)
> >
> >iQEVAwUBQfgfthhoSezw4YfQAQJQKAf8DxKPd+9aXGsomYzRhFPyCcnjEfy6dv/N
> >3GcqV8GR5WyshB207vhvw1PDfZdQVFIXiNr/xE9dmBKEhm38En3a70DnVe2UCmXO
> >UobYXGk9tSW+pnR7Cdd3hc8yeZq0ys+LFKF/sztgpPJji/zFWojPnuS1wCcYggA1
> >kuGCQ9VD6My64Hlh/PStCYqx5C9azgGHNv086W6fQyCssgjwBz51YxdV9gZ9wJUt
> >I8LGjq6T0Fp+5kEEd9SPoUjA+r7bNft3xUPAabb+N4dt8sZUYqzXDP71lYYXgZay
> >z2FE7jkbtX/LYVQCiA4LfgGCbw1sI6p+UQABtj74CPte2CyJZO5hJw==
> >=aHIO
> >-----END PGP SIGNATURE-----
> >
> >_______________________________________________
> >OCCAID Mailing List: http://www.occaid.org
> >schednetisr(NETISR_COFFEE); inq=&coffeebreak_intrq;
> >
> >Occaid at cnacs.occaid.org is the list posting address.
> >db-admin at cnacs.occaid.org is the human contact address.
> >See below URL for subscribe/unsubscribe and list options:
> >http://mailman.twdx.net/mailman/listinfo/occaid
> >
> >
> >
> >
>
> _______________________________________________
> OCCAID Mailing List: http://www.occaid.org
> schednetisr(NETISR_COFFEE); inq=&coffeebreak_intrq;
>
> Occaid at cnacs.occaid.org is the list posting address.
> db-admin at cnacs.occaid.org is the human contact address.
> See below URL for subscribe/unsubscribe and list options:
> http://mailman.twdx.net/mailman/listinfo/occaid
--
James Jun TowardEX Technologies, Inc.
Technical Lead Boston IPv4/IPv6 Web Hosting, Colocation and
james at towardex.com Network design/consulting & configuration services
cell: 1(978)-394-2867 web: http://www.towardex.com , noc: www.twdx.net
More information about the Occaid
mailing list