Denial of service in Cisco ASR 5000 Series

1) Denial of service

EUVDB-ID: #VU1135

Risk: Low

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2016-6455

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote unauthenticated user to cause DoS conditions on the target system.
The weakness is due to insufficient input validation. By sending a specially crafted IPv4 or IPv6 fragmented packets, a remote attacker is able to trigger a flaw in the Slowpath of StarOS for ASR 5500 Series devices with Data Processing Card 2 (DPC2) and reload of the sessmgr service.
Successful exploitation of the vulnerability results in denial of service.

Mitigation

Update fixed versions from the vendor's website.

Vulnerable software versions

Cisco ASR 5000 Series: 18.7.4 - 21.2.A0.65147

External links

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20161102-asr

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.