Cisco IOS XE Software Web UI Command Injection Vulnerability

published 2021-03-24 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-6902

cvss: 6.6; version 3.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 8.5%; EPSS 8.5% chance of exploitation in 30 days, percentile 95%
public exploits: 0; none known

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.

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 2 y ago (2023-11-15)

Exploit prediction

8.54% chance of exploitation in the next 30 days, higher than 95% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.0	6.6	CVSS:3.0/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H
NVD	3.1	7.2	CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	9.0	AV:N/AC:L/Au:S/C:C/I:C/A:C

Affected products

Cisco Cisco IOS XE Software

Classification

Weakness

CWE-22 Improper Limitation of a Pathname to a Restricted Directory

Technology feeds

Cisco IOS rss critical rss

References

tools.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-webcmdinjsh-UFJxTgZD
vendor-advisory

Sources

CVE List CVE-2021-1435
NVD CVE-2021-1435

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Summary