How severe is CVE-2021-34729?

CVE-2021-34729 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-2021-34729 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-34729?

CVE-2021-34729 primarily affects Cisco Ios Xe. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-34729?

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

When was CVE-2021-34729 published?

CVE-2021-34729 was published on 2021-09-23 and last updated on 2026-06-17.

CVE-2021-34729

CVE-2021-34729 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-78.

Key facts

Severity: Medium (CVSS 3.x base score 6.7)
CVSS v2: 7.2
EPSS exploit prediction: 0% (27th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-78
Affected product: Cisco Ios Xe
Published: 2021-09-23
Last modified: 2026-06-17

Description

A vulnerability in the CLI of Cisco IOS XE SD-WAN Software and Cisco IOS XE Software could allow an authenticated, local attacker to execute arbitrary commands with elevated privileges on an affected device. This vulnerability is due to insufficient validation of arguments passed to certain CLI commands. An attacker could exploit this vulnerability by including malicious input in the argument of an affected command. A successful exploit could allow the attacker to execute arbitrary commands with elevated privileges on the underlying operating system. An attacker would need valid user credentials to exploit this vulnerability.

Frequently asked questions

What is CVE-2021-34729?: A vulnerability in the CLI of Cisco IOS XE SD-WAN Software and Cisco IOS XE Software could allow an authenticated, local attacker to execute arbitrary commands with elevated privileges on an affected device. This vulnerability is due to insufficient validation of arguments passed to certain CLI commands. An attacker could exploit this vulnerability by including malicious input in the argument of an affected command. A successful exploit could allow the attacker to execute arbitrary commands with elevated privileges on the underlying operating system. An attacker would need valid user credentials to exploit this vulnerability.
How severe is CVE-2021-34729?: CVE-2021-34729 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-2021-34729 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-34729?: CVE-2021-34729 primarily affects Cisco Ios Xe. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-34729?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-34729 published?: CVE-2021-34729 was published on 2021-09-23 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ioxesdwan-clicmdinj-7bYX5k3

Affected products (2)

cpe:2.3:o:cisco:ios_xe:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:ios_xe_sd-wan:*:*:*:*:*:*:*:*

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