How severe is CVE-2021-34723?

CVE-2021-34723 has a CVSS 3.x base score of 6.7, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-34723 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-34723?

CVE-2021-34723 affects Cisco Ios Xe. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-34723?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-34723 published?

CVE-2021-34723 was published on 2021-09-23 and last updated on 2026-06-17.

CVE-2021-34723

CVE-2021-34723 is a medium-severity vulnerability in Cisco Ios Xe with a CVSS 3.x base score of 6.7. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-668.

Key facts

Severity: Medium (CVSS 3.x base score 6.7)
CVSS v2: 6.9
EPSS exploit prediction: 0% (15th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-668
Affected product: Cisco Ios Xe
Published: 2021-09-23
Last modified: 2026-06-17

Description

A vulnerability in a specific CLI command that is run on Cisco IOS XE SD-WAN Software could allow an authenticated, local attacker to overwrite arbitrary files in the configuration database of an affected device. This vulnerability is due to insufficient validation of specific CLI command parameters. An attacker could exploit this vulnerability by issuing that command with specific parameters. A successful exploit could allow the attacker to overwrite the content of the configuration database and gain root-level access to an affected device.

Frequently asked questions

What is CVE-2021-34723?: A vulnerability in a specific CLI command that is run on Cisco IOS XE SD-WAN Software could allow an authenticated, local attacker to overwrite arbitrary files in the configuration database of an affected device. This vulnerability is due to insufficient validation of specific CLI command parameters. An attacker could exploit this vulnerability by issuing that command with specific parameters. A successful exploit could allow the attacker to overwrite the content of the configuration database and gain root-level access to an affected device.
How severe is CVE-2021-34723?: CVE-2021-34723 has a CVSS 3.x base score of 6.7, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-34723 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (15th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-34723?: CVE-2021-34723 affects Cisco Ios Xe. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-34723?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-34723 published?: CVE-2021-34723 was published on 2021-09-23 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxesdwan-arbfileov-MVOF3ZZn

Affected products (1)

cpe:2.3:o:cisco:ios_xe:17.3.1a:*:*:*:*:*:*:*

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