How severe is CVE-2021-34716?

CVE-2021-34716 has a CVSS 3.x base score of 6.7, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability low.

Is CVE-2021-34716 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-34716?

CVE-2021-34716 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-2021-34716?

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

When was CVE-2021-34716 published?

CVE-2021-34716 was published on 2021-08-18 and last updated on 2026-06-17.

CVE-2021-34716

CVE-2021-34716 is a medium-severity vulnerability in Cisco Expressway 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-755.

Key facts

Severity: Medium (CVSS 3.x base score 6.7)
CVSS v2: 9.0
EPSS exploit prediction: 2% (82nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-755
Affected product: Cisco Expressway
Published: 2021-08-18
Last modified: 2026-06-17

Description

A vulnerability in the web-based management interface of Cisco Expressway Series and Cisco TelePresence Video Communication Server (VCS) could allow an authenticated, remote attacker to execute arbitrary code on the underlying operating system as the root user. This vulnerability is due to incorrect handling of certain crafted software images that are uploaded to the affected device. An attacker could exploit this vulnerability by authenticating to the system as an administrative user and then uploading specific crafted software images to the affected device. A successful exploit could allow the attacker to execute arbitrary code on the underlying operating system as the root user.

Frequently asked questions

What is CVE-2021-34716?: A vulnerability in the web-based management interface of Cisco Expressway Series and Cisco TelePresence Video Communication Server (VCS) could allow an authenticated, remote attacker to execute arbitrary code on the underlying operating system as the root user. This vulnerability is due to incorrect handling of certain crafted software images that are uploaded to the affected device. An attacker could exploit this vulnerability by authenticating to the system as an administrative user and then uploading specific crafted software images to the affected device. A successful exploit could allow the attacker to execute arbitrary code on the underlying operating system as the root user.
How severe is CVE-2021-34716?: CVE-2021-34716 has a CVSS 3.x base score of 6.7, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability low.
Is CVE-2021-34716 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-34716?: CVE-2021-34716 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-2021-34716?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-34716 published?: CVE-2021-34716 was published on 2021-08-18 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ewrce-QPynNCjh

Affected products (2)

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

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