Medium 5.9Known exploited (CISA KEV)Published Mar 27, 2018

CVE-2017-12319A vulnerability in the Border Gateway Protocol (BGP) over an Ethernet Virtual Private Network (EVPN) for Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause the device to r…

Updated under an hour ago (2026-10-19 08:50 UTC)

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CISA lists it as known exploited since Mar 3, 2022; federal agencies had to remediate by Mar 24, 2022. Treat that date as your deadline.

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Exploited in the last 30 days

A vulnerability in the Border Gateway Protocol (BGP) over an Ethernet Virtual Private Network (EVPN) for Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause the device to reload, resulting in a denial of service (DoS) condition, or potentially corrupt the BGP routing table, which could result in network instability. The vulnerability exists due to changes in the implementation of the BGP MPLS-Based Ethernet VPN RFC (RFC 7432) draft between IOS XE software releases. When the BGP Inclusive Multicast Ethernet Tag Route or BGP EVPN MAC/IP Advertisement Route update packet is received, it could be possible that the IP address length field is miscalculated. An attacker could exploit this vulnerability by sending a crafted BGP packet to an affected device after the BGP session was established. An exploit could allow the attacker to cause the affected device to reload or corrupt the BGP routing table; either outcome would result in a DoS. The vulnerability may be triggered when the router receives a crafted BGP message from a peer on an existing BGP session. This vulnerability affects all releases of Cisco IOS XE Software prior to software release 16.3 that support BGP EVPN configurations. If the device is not configured for EVPN, it is not vulnerable. Cisco Bug IDs: CSCui67191, CSCvg52875.

CVSS: 5.9 MEDIUM (v3.1, CISA ADP)CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-20
Known exploited: Added to CISA KEV Mar 3, 2022; federal remediation due Mar 24, 2022Apply updates per vendor instructions.
EPSS (exploitation in the next 30 days): 5.24% (percentile 92)
Assigned by: cisco
NVD analysis: Analyzed
Record last updated: Jan 12, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

cisco ios cisco:ios	15.4(1)s	NVD
cisco ios_xe cisco:ios_xe	before 16.3	NVD

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20171103-bgpx-refsource-confirm, vendor-advisory
http://www.securityfocus.com/bid/101676vdb-entry, x-refsource-bid, broken-link, third-party-advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2017-12319us-government-resource

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.