How severe is CVE-2021-34715?

CVE-2021-34715 has a CVSS 3.x base score of 4.7, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2021-34715 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-34715?

CVE-2021-34715 primarily affects Cisco Expressway. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-34715?

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

When was CVE-2021-34715 published?

CVE-2021-34715 was published on 2021-08-18 and last updated on 2026-06-17.

CVE-2021-34715

CVE-2021-34715 is a medium-severity vulnerability in Cisco Expressway with a CVSS 3.x base score of 4.7. 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-347.

Key facts

Severity: Medium (CVSS 3.x base score 4.7)
CVSS v2: 9.0
EPSS exploit prediction: 1% (60th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-347
Affected product: Cisco Expressway
Published: 2021-08-18
Last modified: 2026-06-17

Description

A vulnerability in the image verification function of Cisco Expressway Series and Cisco TelePresence Video Communication Server (VCS) could allow an authenticated, remote attacker to execute code with internal user privileges on the underlying operating system. The vulnerability is due to insufficient validation of the content of upgrade packages. An attacker could exploit this vulnerability by uploading a malicious archive to the Upgrade page of the administrative web interface. A successful exploit could allow the attacker to execute code with user-level privileges (the _nobody account) on the underlying operating system.

Frequently asked questions

What is CVE-2021-34715?: A vulnerability in the image verification function of Cisco Expressway Series and Cisco TelePresence Video Communication Server (VCS) could allow an authenticated, remote attacker to execute code with internal user privileges on the underlying operating system. The vulnerability is due to insufficient validation of the content of upgrade packages. An attacker could exploit this vulnerability by uploading a malicious archive to the Upgrade page of the administrative web interface. A successful exploit could allow the attacker to execute code with user-level privileges (the _nobody account) on the underlying operating system.
How severe is CVE-2021-34715?: CVE-2021-34715 has a CVSS 3.x base score of 4.7, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2021-34715 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (60th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-34715?: CVE-2021-34715 primarily affects Cisco Expressway. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-34715?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-34715 published?: CVE-2021-34715 was published on 2021-08-18 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ewver-c6WZPXRx

Affected products (2)

cpe:2.3:a:cisco:expressway:*:*:*:*:*:*:*:*
cpe:2.3:a:cisco:telepresence_video_communication_server:*:*:*:*:*:*:*:*

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