Vulnerability identifier: #VU8715

Vulnerability risk: Low

CVSSv3.1: 4.6 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-12270

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Cisco IOS XR
Operating systems & Components / Operating system

Vendor: Cisco Systems, Inc

Description
The vulnerability allows a remote attacker to cause DoS condition on the target system.

The weakness exists in the gRPC code of Cisco IOS XR Software for Cisco Network Convergence System (NCS) 5500 Series Routers due to the software's inability to process HTTP/2 packets. A remote attacker can send a specially crafted HTTP/2 frame and cause the emsd service stops.

Successful exploitation of the vulnerability results in denial of service.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Cisco IOS XR: 6.1.1

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External links
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20171004-ncs

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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.