CVE-2021-1435
Cisco IOS XE Software Web UI Command Injection Vulnerability
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- High
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
6.6
Cisco IOS XE Software Web UI Command Injection Vulnerability
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.
- Record
CVE-2021-1435- CVSS 3.0
- 6.6 Medium
CVSS:3.0/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-22
- Updated
- 2026-11-02
EUVDEUVD-2021-6902
6.6
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.
- Record
EUVD-2021-6902- CVSS 3.0
- 6.6 Medium
CVSS:3.0/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-5rv2-fphg-fgcg No score
A vulnerability in the web UI of Cisco IOS XE Software could allow an authenticated, remote...
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.
- Record
GHSA-5rv2-fphg-fgcg- Weakness
- CWE-22
- Updated
- 2026-11-02
NVD
7.2
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.
- Record
CVE-2021-1435- CVSS 3.1
- 7.2 High
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H - CVSS 3.0
- 6.6 Medium
CVSS:3.0/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 9.0 High
AV:N/AC:L/Au:S/C:C/I:C/A:C - Weakness
- CWE-22
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-1435 is a medium vulnerability (CVSS 6.6) in Cisco Ios Xe Software, published March 24, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 8.54%, the 95th percentile. No source names a fixed version.