CVE-2019-1918 Cisco IOS XR Software Intermediate System–to–Intermediate System Denial of Service Vulnerability
An unauthenticated attacker in the same IS-IS area can cause a denial of service by sending malicious link-state PDUs to Cisco IOS XR devices.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2019-1918?
CVE-2019-1918 is a high-severity denial of service vulnerability in Cisco Ios Xr, published on 7 Aug 2019. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
A vulnerability in the implementation of Intermediate System–to–Intermediate System (IS–IS) routing protocol functionality in Cisco IOS XR Software could allow an unauthenticated attacker who is in the same IS-IS area to cause a denial of service (DoS) condition. The vulnerability is due to incorrect processing of IS–IS link-state protocol data units (PDUs). An attacker could exploit this vulnerability by sending specific link-state PDUs to an affected system to be processed. A successful exploit could allow the attacker to cause incorrect calculations used in the weighted remote shared risk link groups (SRLG) or in the IGP Flexible Algorithm. It could also cause tracebacks to the logs or potentially cause the receiving device to crash the IS–IS process, resulting in a DoS condition.
Which versions are affected by CVE-2019-1918?
It affects 2 products.
Products include Cisco Carrier Routing System, Cisco Ios Xr.
How do I fix CVE-2019-1918?
No fix has been published for CVE-2019-1918 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-2019-1918 being exploited?
There is no known exploitation of CVE-2019-1918 in the wild and no public exploit code.
Other vulnerabilities in Cisco Ios Xr
Sources
Also known as GHSA-29rc-5w3j-4hr7.