CVE-2017-12319
Cisco IOS XE Software Ethernet Virtual Private Network Border Gateway Protocol Denial-of-Service Vulnerability
This vulnerability is in the CISA Known Exploited Vulnerabilities catalog: attackers are using it. If you run IOS XE Software, fix it now.
CISA required action: Apply updates per vendor instructions.
US federal civilian agencies must remediate by Mar 24, 2022.
Patch status
No official fix confirmed yet
Until a fix ships, follow the vendor's mitigations and CISA's required action, limit exposure of affected systems, and watch this record for a patch.
Description
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.
Source: NIST National Vulnerability Database. Official vulnerability data, reproduced as published.
Affected products
| Product | Vendor | Affected versions | Fixed in | Source |
|---|---|---|---|---|
| Cisco networking & security | Cisco | < 16.3 | 16.3 | NVD |
| IOS | Cisco | 15.4\(1\)s | — | NVD |
| IOS XE Software | Cisco | — | — | KEV |
Sources: NVD = NIST National Vulnerability Database; KEV = CISA Known Exploited Vulnerabilities catalog.
Intelligence timeline
Developments from the last 30 days, newest first.
- CVSS scoredUpdateKEV
CVE-2017-12319 scored CVSS 5.9: Cisco IOS XE Software, Cisco IOS XE Software Ethernet Virtual Private Network Border Gateway Protocol Denial-of-Service Vulnerability
CISA lists this as exploited in the wild. Unpatched IOS XE Software systems are exposed to active attacks now.
Basis: NIST National Vulnerability Database
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Coverage
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