CVE-2021-1376
Cisco IOS XE Software Fast Reload Vulnerabilities
- Published
- Updated
- Reserved
- Assigned by
- cisco
Description
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.
Timeline
ID reserved
By cisco
- 4 months later
· 4 months later
Published
- 4 years later
· 4 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| ciscoCNA (assigner) | 3.0 | Medium6.7 | CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | Medium6.7 | CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.24% · top 85% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.7.
Weakness
Affected products
- affected n/a
What to do
Exploitation: The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerabilities that are described in this advisory.
References (1)
- 20210324 Cisco IOS XE Software Fast Reload Vulnerabilities (opens in a new tab)vendor-advisoryx_refsource_CISCOx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2021-1376)Record last updated .