CVE-2019-16018 Cisco IOS XR Software EVPN Operational Routes Denial of Service Vulnerability
Remote attackers can cause a denial of service in Cisco IOS XR by sending malformed BGP EVPN messages, requiring a valid peer connection.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2019-16018?
CVE-2019-16018 is a high-severity denial of service vulnerability in Cisco Ios Xr, published on 26 Jan 2020. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
A vulnerability in the implementation of Border Gateway Protocol (BGP) Ethernet VPN (EVPN) functionality in Cisco IOS XR Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to incorrect processing of a BGP update message that contains crafted EVPN attributes. An attacker could indirectly exploit the vulnerability by sending BGP EVPN update messages with a specific, malformed attribute to an affected system and waiting for a user on the device to display the EVPN operational routes’ status. If successful, the attacker could cause the BGP process to restart unexpectedly, resulting in a DoS condition. The Cisco implementation of BGP accepts incoming BGP traffic only from explicitly defined peers. To exploit this vulnerability, the malicious BGP update message would need to come from a configured, valid BGP peer, or would need to be injected by the attacker into the victim's BGP network on an existing, valid TCP connection to a BGP peer.
Which versions are affected by CVE-2019-16018?
It affects 1 product.
Products include Cisco Ios Xr.
How do I fix CVE-2019-16018?
No fix has been published for CVE-2019-16018 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2019-16018 being exploited?
There is no known exploitation of CVE-2019-16018 in the wild and no public exploit code.
Other vulnerabilities in Cisco Ios Xr
- CVE-2020-3118 Cisco IOS XR Software Discovery Protocol Format String
- CVE-2020-3569 Cisco IOS XR Software DVMRP Memory Exhaustion
- CVE-2020-3566 Cisco IOS XR Software DVMRP Memory Exhaustion
- CVE-2010-3035 Cisco IOS XR Border Gateway Protocol (BGP) Denial-of-Service
- CVE-2022-20821 Cisco IOS XR Open Port
Sources
Also known as GHSA-638h-mp9x-p4wm.