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

Exploited · KEV 2022-03-03CVE-2017-12319CWE-20

Exploited since 2022-03-03. No WAF vendor names it yet.

Edge rules

0/8

Our test

No exploit yet

CVSS

5.9

EPSS

5.2% Top 7%

Posts, 14d

Published

2018-03-27

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.

Edge coverage

Claimed by vendors

CloudflareBefore feed historyOlder than its feed AWSBefore feed historyOlder than its feed Microsoft AzureNo public claimNot named Google CloudBefore feed historyOlder than its feed FastlyBefore feed historyOlder than its feed F5Before feed historyOlder than its feed AkamaiNo public sourceNo public changelog OWASP CRSBefore feed historyOlder than its feed

Ask Vigil

AI · answers from this page

Ask about CVE-2017-12319: who's covered, what to patch first, how vendors compare. I cite sources and won't help with attacks.

Workers AI (Llama 3.3). Can be wrong: check the cited source.

Severity, decoded

CVSS 3.1

5.9Medium

Medium · 5.9 / 10

Exploitable over the network under specific conditions, with no privileges and no user interaction, leading to full loss of availability.

Over the internetNo login neededNo user actionHard to pull offSerious impact

How the score is built8 metrics

Attack vectorAn attacker can reach it over the internet; no access to your network needed.
Network
Attack complexityThe attack only works when conditions outside the attacker's control line up.
High
Privileges requiredNo account or login is needed.
None
User interactionNo one has to click or open anything; the attack works on its own.
None
ScopeThe damage stays within the vulnerable component.
Unchanged
Confidentiality impactNo data is exposed.
None
Integrity impactData cannot be changed by the attacker.
None
Availability impactAn attacker can take the component down completely or keep it from serving anyone.
High

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA's assessmentSSVC, from the CVE record

ExploitationActive

Attackers are exploiting this in the wild.

AutomatableYes

Attackers can script the attack end to end and hit many targets at once.

Technical impactPartial

A successful attack gives limited control over the affected software or limited access to its data.

Public exploits

None found

0 Metasploit0 Exploit-DB0 Scanner template0 GitHub PoCs

No exploit in Exploit-DB or Metasploit, and no scanner template. That lowers, but doesn't remove, the chance of mass exploitation.

Timeline

2018-03-27
CVE published
CVE List
2022-03-03
Added to CISA KEV
Confirmed exploitation in the wild