CVE-2017-3859
highpriority · track · 31EPSS 0.025 · 84 %ileEURUUSEPSS · scored 2026-10-27
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.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- Fixed3.13.5aScisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.13.6Scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.13.6aScisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.13.6bScisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.14.3Scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.14.4Scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.15.1Scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.15.2Scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.15.3Scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.15.4Scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.16.0Scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.16.1aScisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.16.2aScisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.16.2bScisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.16.3Scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.16.3aScisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.17.0Scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.17.1Scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.17.1aScisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.17.2Scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.18.0Scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.18.0SPcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.18.0aScisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.18.1Scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.18.1SPcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.18.1aSPcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.18.1bSPcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.18.1cSPcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.18.1gSPcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.18.1hSPcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.18.1iSPcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed3.18.2Scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco ASR 900 Series Aggregation Services Routerscisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.9–8.6
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (68)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-20170322-ztpCisco IOS XE Software for Cisco ASR 920 Series Routers Zero Touch Provisioning Denial of Service Vulnerability2017-03-22csaf · cisco_csafUS
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. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is part of the March 22, 2017, release of the Cisco IOS and IOS XE Software Security Advisory Bundled Publication, which includes five Cisco Security Advisories that describe five vulnerabilities. All the vulnerabilities have a Security Impact Rating of High. For a complete list of the advisories and links to them, see Cisco Event Response: March 2017 Semiannual Cisco IOS and IOS XE Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-60851"].
also known as (5)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (8)
External citations — patches, advisories, analysis.
- https://bst.cloudapps.cisco.com/bugsearch/bug/CSCuy56385Patchcnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170322-ztpcnnvd
- http://www.securityfocus.com/bid/97008enisa_euvd
- http://www.securitytracker.com/id/1038104enisa_euvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170322-ztpenisa_euvd
- http://www.securityfocus.com/bid/97008Third Party AdvisoryVDB Entrynvd
- http://www.securitytracker.com/id/1038104nvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170322-ztpVendor Advisorynvd
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