Vulnerability identifier: #VU10339

Vulnerability risk: Medium

CVSSv3.1: 7.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2018-0136

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Cisco ASR 9922 Router
Client/Desktop applications / Software for system administration
Cisco ASR 9912 Router
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco ASR 9001 Router
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco ASR 9006 Router
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco ASR 9904 Router
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco ASR 9010 Router
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco ASR 9000 Series Aggregation Services Routers
Hardware solutions / Routers & switches, VoIP, GSM, etc

Vendor: Cisco Systems, Inc

Description

The vulnerability allows a remote attacker to cause DoS condition no the target system.

The vulnerability exists in the IPv6 subsystem due to incorrect handling of IPv6 packets with a fragment header extension. A remote attacker can send specially crafted IPv6 packets designed to trigger the issue either to or through the Trident-based line card and cause the Trident-based line cards to reload during the period of time the line card takes to restart.

Successful exploitation of the vulnerability results in denial of service.

Mitigation
Update to version 5.3.4.

Vulnerable software versions

Cisco ASR 9922 Router: All versions

Cisco ASR 9912 Router: All versions

Cisco ASR 9001 Router: All versions

Cisco ASR 9006 Router: All versions

Cisco ASR 9904 Router: All versions

Cisco ASR 9010 Router: All versions

Cisco ASR 9000 Series Aggregation Services Routers: All versions

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External links
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180131-ipv6

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.