CVE-2021-1435

highpriority · track · 32EPSS 0.085 · 95 %ileEURUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
8.54% (95th) EPSS
CVSS 9 · high
Is it mine?
78 products
Check your exposure
Who says so?
4 sources
cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · scored 2026-10-27

A vulnerability in the web UI of Cisco IOS XE Software could allow an authenticated, remote attacker to inject arbitrary commands that can be executed as the root user. This vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by sending a crafted request to the web UI of an affected device with arbitrary commands injected into a portion of the request. A successful exploit could allow the attacker to execute arbitrary commands 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
v3.06.6mediumCVSS:3.0/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:Hsecondary · ENISA EU
v3.06.6mediumCVSS:3.0/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:Hsecondary · psirt@cisco.com USexploitability 0.7 · impact 5.9
v3.06.6mediumCVSS:3.0/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:Hsecondary · Cisco PSIRT US
v3.16.6mediumAV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU
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)
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-22USCWE-22US
05

affected products (78)

Products and version ranges known to be affected.

showing 20 of 78
06

advisories (1)

Vendor and ecosystem advisories describing this.

  • cisco-sa-iosxe-webcmdinjsh-UFJxTgZDCisco IOS XE Software Web UI Command Injection Vulnerability2021-03-24csaf · cisco_csafUS

    A vulnerability in the web UI of Cisco IOS XE Software could allow an authenticated, remote attacker to inject arbitrary commands that can be executed as the root user. This vulnerability is due to insufficient input validation. An attacker could exploit this vulnerability by sending a crafted request to the web UI of an affected device with arbitrary commands injected into a portion of the request. A successful exploit could allow the attacker to execute arbitrary commands 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_csafNVDCVE.orgMITRE
published 2021-03-24modified 2026-06-17
09

references (6)

External citations — patches, advisories, analysis.

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