CVE-2021-34718: Cisco IOS XR Software Arbitrary File Read and Write Vulnerability
First published: Thu Sep 09 2021(Updated: )
A vulnerability in the SSH Server process of Cisco IOS XR Software could allow an authenticated, remote attacker to overwrite and read arbitrary files on the local device. This vulnerability is due to insufficient input validation of arguments that are supplied by the user for a specific file transfer method. An attacker with lower-level privileges could exploit this vulnerability by specifying Secure Copy Protocol (SCP) parameters when authenticating to a device. A successful exploit could allow the attacker to elevate their privileges and retrieve and upload files on a device that they should not have access to.
Credit: ykramarz@cisco.com
| Affected Software | Affected Version | How to fix |
|---|---|---|
| Cisco IOS XR | <7.3.2 | |
| Cisco IOS XR | >=7.4.0<7.4.1 | |
| Cisco Asr 9000v-v2 | ||
| Cisco Asr 9001 | ||
| Cisco Asr 9006 | ||
| Cisco Asr 9010 | ||
| Cisco Asr 9901 | ||
| Cisco Asr 9902 | ||
| Cisco Asr 9903 | ||
| Cisco Asr 9904 | ||
| Cisco Asr 9906 | ||
| Cisco Asr 9910 | ||
| Cisco Asr 9912 | ||
| Cisco Asr 9922 | ||
| Cisco Ios Xrv | ||
| Cisco Ios Xrv 9000 | ||
| Cisco Ncs 520 | ||
| Cisco Ncs 540 | ||
| Cisco Ncs 540 Fronthaul | ||
| Cisco Ncs 560-4 | ||
| Cisco Ncs 560-7 | ||
| Cisco Ncs 5001 | ||
| Cisco Ncs 5002 | ||
| Cisco Ncs 5011 | ||
| Cisco Ncs 4009 | ||
| Cisco Ncs 4016 | ||
| Cisco Ncs 5501 | ||
| Cisco Ncs 5501-se | ||
| Cisco Ncs 5502 | ||
| Cisco Ncs 5502-se | ||
| Cisco Ncs 5508 | ||
| Cisco Ncs 5516 | ||
| Cisco Ncs 6000 | ||
| Cisco Ncs 6008 | ||
| Cisco Ncs 1001 | ||
| Cisco Ncs 1002 | ||
| Cisco Ncs 1004 |
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Reference Links
Frequently Asked Questions
What is the vulnerability ID for this Cisco IOS XR Software vulnerability?
The vulnerability ID is CVE-2021-34718.
What is the severity of CVE-2021-34718?
The severity of CVE-2021-34718 is high with a CVSS score of 8.1.
How does CVE-2021-34718 affect Cisco IOS XR Software?
CVE-2021-34718 allows an authenticated remote attacker to overwrite and read arbitrary files on the local device.
Which versions of Cisco IOS XR Software are affected by CVE-2021-34718?
Cisco IOS XR Software versions up to and including 7.3.2 are affected. Versions 7.4.0 and 7.4.1 are also affected.
How can CVE-2021-34718 be fixed?
To fix CVE-2021-34718, Cisco IOS XR Software users should apply the necessary updates provided by Cisco.
- collector/nvd-index
- agent/type
- agent/softwarecombine
- collector/mitre-cve
- source/MITRE
- agent/references
- agent/title
- agent/weakness
- agent/author
- agent/severity
- agent/last-modified-date
- agent/tags
- agent/first-publish-date
- agent/event
- agent/description
- vendor/cisco
- canonical/cisco ios xr
- version/cisco ios xr/7.4.0
- canonical/cisco asr 9000v-v2
- canonical/cisco asr 9001
- canonical/cisco asr 9006
- canonical/cisco asr 9010
- canonical/cisco asr 9901
- canonical/cisco asr 9902
- canonical/cisco asr 9903
- canonical/cisco asr 9904
- canonical/cisco asr 9906
- canonical/cisco asr 9910
- canonical/cisco asr 9912
- canonical/cisco asr 9922
- canonical/cisco ios xrv
- canonical/cisco ios xrv 9000
- canonical/cisco ncs 520
- canonical/cisco ncs 540
- canonical/cisco ncs 540 fronthaul
- canonical/cisco ncs 560-4
- canonical/cisco ncs 560-7
- canonical/cisco ncs 5001
- canonical/cisco ncs 5002
- canonical/cisco ncs 5011
- canonical/cisco ncs 4009
- canonical/cisco ncs 4016
- canonical/cisco ncs 5501
- canonical/cisco ncs 5501-se
- canonical/cisco ncs 5502
- canonical/cisco ncs 5502-se
- canonical/cisco ncs 5508
- canonical/cisco ncs 5516
- canonical/cisco ncs 6000
- canonical/cisco ncs 6008
- canonical/cisco ncs 1001
- canonical/cisco ncs 1002
- canonical/cisco ncs 1004