CVE DATABASE / CVE-2017-12319

CVE-2017-12319

Cisco IOS XE Software Ethernet Virtual Private Network Border Gateway Protocol Denial-of-Service Vulnerability

CVSS 5.9 · MEDIUM ⚠ CISA KEV — ACTIVELY EXPLOITED

On the CISA KEV catalog

Confirmed exploited in the wild. Added 2022-03-03. Federal remediation due 2022-03-24.
Required action: Apply updates per vendor instructions.

Summary

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 3.1 breakdown

Base score	5.9 (MEDIUM)
Vector	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector	NETWORK
Attack complexity	HIGH
Privileges required	NONE
User interaction	NONE
Scope	UNCHANGED
Confidentiality	NONE
Integrity	NONE
Availability	HIGH

Weakness type (CWE)

CWE-20

Affected products

Cisco iosCisco ios xeCisco 1000 integrated services routerCisco 1100-4g\/6g integrated services routerCisco 1100-4g integrated services routerCisco 1100-4gltegb integrated services routerCisco 1100-4gltena integrated services routerCisco 1100-4p integrated services routerCisco 1100-6g integrated services routerCisco 1100-8p integrated services routerCisco 1100-lte integrated services routerCisco 1100 integrated services routerCisco 1101-4p integrated services routerCisco 1101 integrated services routerCisco 1109-2p integrated services routerCisco 1109-4p integrated services routerCisco 1109 integrated services routerCisco 1111x-8p integrated services routerCisco 1111x integrated services routerCisco 111x integrated services router

Check this CVE live

Use our free CVE Lookup tool for the latest NVD record, or browse the full CISA KEV catalog.

References

Data: NIST NVD + CISA KEV. NVD last modified 2026-01-13. Always verify against the vendor advisory before acting.