#VU25028 Format string error in Cisco Systems, Inc products - CVE-2020-3118
Published: February 7, 2020 / Updated: February 20, 2022
Cisco ASR 9000 Series Aggregation Services Routers
Cisco IOS XRv 9000 Router
Cisco Network Convergence System 5000 Series
Network Convergence System 5500 Series
Cisco Network Convergence System 540 Series Routers
Cisco Network Convergence System 560 Series Routers
Cisco Network Convergence System 6000 Series Routers
Cisco Carrier Routing System
Cisco Network Convergence System 1000 Series
Cisco Systems, Inc
Description
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to improper validation of string input from certain fields in the Cisco Discovery Protocol implementation for Cisco IOS XR Software. A remote attacker on the local network can supply a specially crafted input that contains format string specifiers, cause a stack overflow and execute arbitrary code with administrative privileges on an affected device.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
Remediation
Install updates from vendor's website.
| Cisco IOS XR Software Release | First Fixed Release for This Vulnerability |
|---|---|
| Earlier than 6.6 | Appropriate SMU |
| 6.61 | 6.6.3 or appropriate SMU |
| 7.0 | 7.0.2 (Mar 2020) or appropriate SMU |
| 7.1 | Not vulnerable |
| Cisco IOS XR Software Release | Platform | SMU Name |
|---|---|---|
| 5.2.5 | NCS6K | ncs6k-5.2.5.CSCvr78185 |
| 6.4.2 | ASR9K-PX | asr9k-px-6.4.2.CSCvr78185 |
| CRS-PX | hfr-px-6.4.2.CSCvr78185 | |
| 6.5.3 | ASR9K-PX | asr9k-px-6.5.3.CSCvr78185 |
| ASR9K-X64 | asr9k-x64-6.5.3.CSCvr78185 | |
| NCS540 | ncs540-6.5.3.CSCvr78185 | |
| NCS5K | ncs5k-6.5.3.CSCvr78185 | |
| NCS5500 | ncs5500-6.5.3.CSCvr78185 | |
| XRV9K | xrv9k-6.5.3.CSCvr78185 | |
| 6.6.12 | White box | iosxrwbd-6.6.12.CSCvr78185 |
| 6.6.25 | NCS560 | ncs560-6.6.25.CSCvr78185 |
| 7.0.1 | NCS540L | ncs540l-7.0.1.CSCvr78185 |