CVE-2021-34716

highpriority · track · 30EPSS 0.024 · 84 %ileEURUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
2.40% (84th) EPSS
CVSS 9 · high
Is it mine?
6 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · scored 2026-10-24

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.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

02

cvss

Technical severity, 0–10. One row per scoring source.

9.0
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.6–9

v2.09highAV:N/AC:L/Au:S/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 8 · impact 10
v3.17.2highCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 1.2 · impact 5.9
v3.16.7mediumAV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:Lsecondary · FSTEC (BDU) RU
v3.16.7mediumCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:Lsecondary · ENISA EU
v3.16.7mediumCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:Lsecondary · psirt@cisco.com USexploitability 1.2 · impact 5.5
v3.16.6mediumCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)
v3.16.7mediumCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:Lsecondary · Cisco PSIRT US
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-755USprimaryCWE-460USCWE-460US
05

affected products (6)

Products and version ranges known to be affected.

06

advisories (1)

Vendor and ecosystem advisories describing this.

  • cisco-sa-ewrce-QPynNCjhCisco Expressway Series and TelePresence Video Communication Server Remote Code Execution Vulnerability2021-08-18csaf · cisco_csafUS

    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. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

07

also known as (4)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducisco_csafnvdNVDCVE.orgMITRE
published 2021-08-18modified 2026-06-17
10

references (5)

External citations — patches, advisories, analysis.

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