CVE-2021-34715
highpriority · track · 29EPSS 0.011 · 64 %ileEURUUSEPSS · scored 2026-10-27
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.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco TelePresence Video Communication Server (VCS) Expresswaycisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.7–9
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (6)
Products and version ranges known to be affected.
- cisco telepresence video communication server≤ x8.8nvdUScpe:2.3:a:cisco:telepresence_video_communication_server:*:*:*:*:*:*:*:*
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-ewver-c6WZPXRxCisco Expressway Series and TelePresence Video Communication Server Image Verification Vulnerability2021-08-18csaf · cisco_csafUS
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. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (5)
External citations — patches, advisories, analysis.
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ewver-c6WZPXRxcnnvd
- https://www.auscert.org.au/bulletins/ESB-2021.2806cnnvd
- https://www.cybersecurity-help.cz/vdb/SB2021082303cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ewver-c6WZPXRxenisa_euvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ewver-c6WZPXRxPatchVendor Advisorynvd
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