CVE-2022-20758 Cisco IOS XR Software Border Gateway Protocol Ethernet VPN Denial of Service Vulnerability
Remote attackers with valid BGP peer access can cause a denial of service by sending malicious EVPN update messages to Cisco IOS XR devices.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2022-20758?
CVE-2022-20758 is a medium-severity denial of service vulnerability in Cisco Ios Xr, published on 15 Apr 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A vulnerability in the implementation of the 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. This vulnerability is due to the incorrect processing of a BGP update message that contains specific EVPN attributes. An attacker could exploit this vulnerability by sending a BGP update message that contains specific EVPN attributes. To exploit this vulnerability, an attacker must control a BGP speaker that has an established trusted peer connection to an affected device that is configured with the address family L2VPN EVPN to receive and process the update message. This vulnerability cannot be exploited by any data that is initiated by clients on the Layer 2 network or by peers that are not configured to accept the L2VPN EVPN address family. A successful exploit could allow the attacker to cause the BGP process to restart unexpectedly, resulting in a DoS condition. The Cisco implementation of BGP accepts incoming BGP updates only from explicitly defined peers. For this vulnerability to be exploited, the malicious BGP update message must either come from a configured, valid BGP peer or be injected by the attacker into the affected BGP network on an existing, valid TCP connection to a BGP peer.
Weakness: CWE-399
Which versions are affected by CVE-2022-20758?
It affects 1 product.
Products include Cisco Ios Xr.
How do I fix CVE-2022-20758?
No fix has been published for CVE-2022-20758 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-2022-20758 being exploited?
There is no known exploitation of CVE-2022-20758 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-786f-rrh2-r2pf.