Cisco ASR 920 up to 3.18 Zero Touch Provisioning format string

CVSS Meta Temp Score
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7.1$0-$5k0.00

A vulnerability, which was classified as critical, has been found in Cisco ASR 920 up to 3.18 (Router Operating System). This issue affects an unknown part of the component Zero Touch Provisioning. The manipulation with an unknown input leads to a format string vulnerability. Using CWE to declare the problem leads to CWE-134. The product uses a function that accepts a format string as an argument, but the format string originates from an external source. Impacted is availability. The summary by CVE is:

A vulnerability in the DHCP code for the Zero Touch Provisioning feature of Cisco ASR 920 Series Aggregation Services Routers could allow an unauthenticated, remote attacker to cause an affected device to reload. The vulnerability is due to a format string vulnerability when processing a crafted DHCP packet for Zero Touch Provisioning. An attacker could exploit this vulnerability by sending a specially crafted DHCP packet to an affected device. An exploit could allow the attacker to cause the device to reload, resulting in a denial of service (DoS) condition. This vulnerability affects Cisco ASR 920 Series Aggregation Services Routers that are running an affected release of Cisco IOS XE Software (3.13 through 3.18) and are listening on the DHCP server port. By default, the devices do not listen on the DHCP server port. Cisco Bug IDs: CSCuy56385.

The bug was discovered 03/22/2017. The weakness was released 03/22/2017 with Cisco as cisco-sa-20170322-ztp as confirmed advisory (Website). The advisory is shared at tools.cisco.com. The identification of this vulnerability is CVE-2017-3859 since 12/21/2016. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 99033 (Cisco IOS XE for Cisco ASR 920 Series Routers Zero Touch Provisioning DoS (cisco-sa-20170322-ztp)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family CISCO and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 316340 (Cisco IOS XE Software for Cisco ASR 920 Series Routers Zero Touch Provisioning Denial of Service Vulnerability(cisco-sa-20170322-ztp)).

Upgrading eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (99033) and SecurityFocus (BID 97008†). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.1
VulDB Meta Temp Score: 7.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

Vendor Base Score (Cisco): 8.6
Vendor Vector (Cisco): 🔍

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
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NVD Base Score: 🔍

Exploitinginfo

Class: Format string
CWE: CWE-134 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 99033
Nessus Name: Cisco IOS XE for Cisco ASR 920 Series Routers Zero Touch Provisioning DoS (cisco-sa-20170322-ztp)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 103403
OpenVAS Name: Cisco IOS XE Software for Cisco ASR 920 Series Routers Zero Touch Provisioning Denial of Service Vulnerability
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Timelineinfo

12/21/2016 🔍
03/22/2017 +91 days 🔍
03/22/2017 +0 days 🔍
03/22/2017 +0 days 🔍
03/22/2017 +0 days 🔍
03/22/2017 +0 days 🔍
03/23/2017 +1 days 🔍
03/29/2017 +6 days 🔍
11/14/2022 +2056 days 🔍

Sourcesinfo

Vendor: cisco.com

Advisory: cisco-sa-20170322-ztp
Organization: Cisco
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-3859 (🔍)
GCVE (CVE): GCVE-0-2017-3859
GCVE (VulDB): GCVE-100-98381

OVAL: 🔍

SecurityFocus: 97008 - Cisco IOS XE Software CVE-2017-3859 Denial of Service Vulnerability
OSVDB: - CVE-2017-3859 - Cisco - ASR 920 - Denial of Service Issue
SecurityTracker: 1038104

Entryinfo

Created: 03/23/2017 07:56 AM
Updated: 11/14/2022 12:17 PM
Changes: 03/23/2017 07:56 AM (85), 09/10/2020 10:26 PM (8), 11/14/2022 12:17 PM (3)
Complete: 🔍
Cache ID: 18:370:40

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