CVE-2021-1375
Cisco IOS XE Software Fast Reload Vulnerabilities
Multiple vulnerabilities in the fast reload feature of Cisco IOS XE Software running on Cisco Catalyst 3850, Cisco Catalyst 9300, and Cisco Catalyst 9300L Series Switches could allow an authenticated, local attacker to either execute arbitrary code on the underlying operating system, install and boot a malicious software image, or execute unsigned binaries on an affected device. These vulnerabilities are due to improper checks performed by system boot routines. To exploit these vulnerabilities, the attacker would need privileged access to the CLI of the device. A successful exploit could allow the attacker to either execute arbitrary code on the underlying operating system or execute unsigned code and bypass the image verification check part of the secure boot process. For more information about these vulnerabilities, see the Details section of this advisory.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- 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
6.7
Cisco IOS XE Software Fast Reload Vulnerabilities
Multiple vulnerabilities in the fast reload feature of Cisco IOS XE Software running on Cisco Catalyst 3850, Cisco Catalyst 9300, and Cisco Catalyst 9300L Series Switches could allow an authenticated, local attacker to either execute arbitrary code on the underlying operating system, install and boot a malicious software image, or execute unsigned binaries on an affected device. These vulnerabilities are due to improper checks performed by system boot routines. To exploit these vulnerabilities, the attacker would need privileged access to the CLI of the device. A successful exploit could allow the attacker to either execute arbitrary code on the underlying operating system or execute unsigned code and bypass the image verification check part of the secure boot process. For more information about these vulnerabilities, see the Details section of this advisory.
- Record
CVE-2021-1375- CVSS 3.0
- 6.7 Medium
CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-347
- Updated
- 2026-11-02
EUVDEUVD-2021-6842
6.7
Multiple vulnerabilities in the fast reload feature of Cisco IOS XE Software running on Cisco Catalyst 3850, Cisco Catalyst 9300, and Cisco Catalyst 9300L Series Switches could allow an authenticated, local attacker to either execute arbitrary code on the underlying operating system, install and boot a malicious software image, or execute unsigned binaries on an affected device. These vulnerabilities are due to improper checks performed by system boot routines. To exploit these vulnerabilities, the attacker would need privileged access to the CLI of the device. A successful exploit could allow the attacker to either execute arbitrary code on the underlying operating system or execute unsigned code and bypass the image verification check part of the secure boot process. For more information about these vulnerabilities, see the Details section of this advisory.
- Record
EUVD-2021-6842- CVSS 3.0
- 6.7 Medium
CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-4c73-wx52-99cm No score
Multiple vulnerabilities in the fast reload feature of Cisco IOS XE Software running on Cisco...
Multiple vulnerabilities in the fast reload feature of Cisco IOS XE Software running on Cisco Catalyst 3850, Cisco Catalyst 9300, and Cisco Catalyst 9300L Series Switches could allow an authenticated, local attacker to either execute arbitrary code on the underlying operating system, install and boot a malicious software image, or execute unsigned binaries on an affected device. These vulnerabilities are due to improper checks performed by system boot routines. To exploit these vulnerabilities, the attacker would need privileged access to the CLI of the device. A successful exploit could allow the attacker to either execute arbitrary code on the underlying operating system or execute unsigned code and bypass the image verification check part of the secure boot process. For more information about these vulnerabilities, see the Details section of this advisory.
- Record
GHSA-4c73-wx52-99cm- Weakness
- CWE-347
- Updated
- 2026-11-02
NVD
6.7
Multiple vulnerabilities in the fast reload feature of Cisco IOS XE Software running on Cisco Catalyst 3850, Cisco Catalyst 9300, and Cisco Catalyst 9300L Series Switches could allow an authenticated, local attacker to either execute arbitrary code on the underlying operating system, install and boot a malicious software image, or execute unsigned binaries on an affected device. These vulnerabilities are due to improper checks performed by system boot routines. To exploit these vulnerabilities, the attacker would need privileged access to the CLI of the device. A successful exploit could allow the attacker to either execute arbitrary code on the underlying operating system or execute unsigned code and bypass the image verification check part of the secure boot process. For more information about these vulnerabilities, see the Details section of this advisory.
- Record
CVE-2021-1375- CVSS 3.1
- 6.7 Medium
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H - CVSS 3.0
- 6.7 Medium
CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 7.2 High
AV:L/AC:L/Au:N/C:C/I:C/A:C - Weakness
- CWE-347
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-1375 is a medium vulnerability (CVSS 6.7) 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 0.24%, the 15th percentile. No source names a fixed version.