{"schemaVersion":3,"id":"CVE-2021-1376","aliases":[],"status":"published","duplicateOf":null,"title":null,"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.","dates":{"published":"2021-03-24T20:15:33.955Z","modified":"2024-11-08T23:32:25.328Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":7.2,"severity":"high","version":"2.0","versionLabel":"v2.0","source":"NVD","vector":"AV:L/AC:L/Au:N/C:C/I:C/A:C","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.0","versionLabel":"v3.0","source":"CVE.org","score":6.7,"severity":"medium","vector":"CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":6.7,"severity":"medium","vector":"CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false},{"version":"3.0","versionLabel":"v3.0","source":"NVD","score":6.7,"severity":"medium","vector":"CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false},{"version":"2.0","versionLabel":"v2.0","source":"NVD","score":7.2,"severity":"high","vector":"AV:L/AC:L/Au:N/C:C/I:C/A:C","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.0024,"percentile":0.1429,"severity":"low","asOf":"2026-10-21T00:00:00.000Z","change":{"pp":0.007999999999999978,"baselineDate":"2026-09-21T00:00:00.000Z","baselineScore":0.00232},"history":[{"date":"2026-09-14T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-15T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-16T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.0024,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.0024,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.0024,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.0024,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.0024,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.0024,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.0024,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.0024,"percentile":null},{"date":"2026-10-21T00:00:00.000Z","score":0.0024,"percentile":0.1429}],"last30":[{"date":"2026-09-21T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.00232,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.0024,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.0024,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.0024,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.0024,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.0024,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.0024,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.0024,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.0024,"percentile":null},{"date":"2026-10-21T00:00:00.000Z","score":0.0024,"percentile":0.1429}]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[],"exploitCount":0,"weaknesses":[{"id":"CWE-347","name":"Improper Verification of Cryptographic Signature","description":"The product does not verify, or incorrectly verifies, the cryptographic signature for data.","type":"weakness","status":"Draft","abstraction":"Base","likelihoodOfExploit":null,"url":"https://cwe.mitre.org/data/definitions/347.html"}],"affected":[{"vendor":"cisco","product":"cisco ios xe software","name":"Cisco IOS XE Software","label":"cisco ios xe software","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"n/a","noFixRecorded":false,"fixedIn":null}],"versionsText":"n/a","eol":null,"hubHref":"/vendor/cisco/cisco_ios_xe_software"},{"vendor":"cisco","product":"ios_xe","name":"ios xe","label":"ios_xe","ecosystem":null,"cpePart":"o","purl":null,"purlType":null,"versions":[{"text":"16.5.1","noFixRecorded":false,"fixedIn":null},{"text":"16.5.1a","noFixRecorded":false,"fixedIn":null},{"text":"16.6.1","noFixRecorded":false,"fixedIn":null},{"text":"16.6.2","noFixRecorded":false,"fixedIn":null},{"text":"16.6.3","noFixRecorded":false,"fixedIn":null},{"text":"16.6.4","noFixRecorded":false,"fixedIn":null},{"text":"16.6.4a","noFixRecorded":false,"fixedIn":null},{"text":"16.6.4s","noFixRecorded":false,"fixedIn":null},{"text":"16.6.5","noFixRecorded":false,"fixedIn":null},{"text":"16.6.6","noFixRecorded":false,"fixedIn":null},{"text":"16.6.7","noFixRecorded":false,"fixedIn":null},{"text":"16.6.8","noFixRecorded":false,"fixedIn":null},{"text":"16.8.1","noFixRecorded":false,"fixedIn":null},{"text":"16.8.1a","noFixRecorded":false,"fixedIn":null},{"text":"16.8.1s","noFixRecorded":false,"fixedIn":null},{"text":"16.9.1","noFixRecorded":false,"fixedIn":null},{"text":"16.9.1s","noFixRecorded":false,"fixedIn":null},{"text":"16.9.2","noFixRecorded":false,"fixedIn":null},{"text":"16.9.2s","noFixRecorded":false,"fixedIn":null},{"text":"16.9.3","noFixRecorded":false,"fixedIn":null},{"text":"16.9.3a","noFixRecorded":false,"fixedIn":null},{"text":"16.9.3s","noFixRecorded":false,"fixedIn":null},{"text":"16.9.4","noFixRecorded":false,"fixedIn":null},{"text":"16.9.5","noFixRecorded":false,"fixedIn":null},{"text":"16.9.6","noFixRecorded":false,"fixedIn":null},{"text":"16.10.1","noFixRecorded":false,"fixedIn":null},{"text":"16.10.1e","noFixRecorded":false,"fixedIn":null},{"text":"16.10.1s","noFixRecorded":false,"fixedIn":null},{"text":"16.11.1","noFixRecorded":false,"fixedIn":null},{"text":"16.11.1b","noFixRecorded":false,"fixedIn":null},{"text":"16.11.1c","noFixRecorded":false,"fixedIn":null},{"text":"16.11.1s","noFixRecorded":false,"fixedIn":null},{"text":"16.11.2","noFixRecorded":false,"fixedIn":null},{"text":"16.12.1","noFixRecorded":false,"fixedIn":null},{"text":"16.12.1c","noFixRecorded":false,"fixedIn":null},{"text":"16.12.1s","noFixRecorded":false,"fixedIn":null},{"text":"16.12.2","noFixRecorded":false,"fixedIn":null},{"text":"16.12.2s","noFixRecorded":false,"fixedIn":null},{"text":"16.12.2t","noFixRecorded":false,"fixedIn":null},{"text":"16.12.3","noFixRecorded":false,"fixedIn":null},{"text":"16.12.3a","noFixRecorded":false,"fixedIn":null},{"text":"16.12.3s","noFixRecorded":false,"fixedIn":null},{"text":"16.12.4","noFixRecorded":false,"fixedIn":null},{"text":"16.12.4a","noFixRecorded":false,"fixedIn":null},{"text":"17.1.1","noFixRecorded":false,"fixedIn":null},{"text":"17.1.1s","noFixRecorded":false,"fixedIn":null},{"text":"17.1.1t","noFixRecorded":false,"fixedIn":null},{"text":"17.1.2","noFixRecorded":false,"fixedIn":null},{"text":"17.2.1","noFixRecorded":false,"fixedIn":null},{"text":"17.2.1a","noFixRecorded":false,"fixedIn":null}],"versionsText":"16.5.1 | 16.5.1a | 16.6.1 | 16.6.2 | 16.6.3 | 16.6.4 | 16.6.4a | 16.6.4s | 16.6.5 | 16.6.6 | 16.6.7 | 16.6.8 | 16.8.1 | 16.8.1a | 16.8.1s | 16.9.1 | 16.9.1s | 16.9.2 | 16.9.2s | 16.9.3 | 16.9.3a | 16.9.3s | 16.9.4 | 16.9.5 | 16.9.6 | 16.10.1 | 16.10.1e | 16.10.1s | 16.11.1 | 16.11.1b | 16.11.1c | 16.11.1s | 16.11.2 | 16.12.1 | 16.12.1c | 16.12.1s | 16.12.2 | 16.12.2s | 16.12.2t | 16.12.3 | 16.12.3a | 16.12.3s | 16.12.4 | 16.12.4a | 17.1.1 | 17.1.1s | 17.1.1t | 17.1.2 | 17.2.1 | 17.2.1a","eol":null,"hubHref":"/vendor/cisco/ios_xe"}],"affectedCount":2,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fast-Zqr6DD5","label":"tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fast-Zqr6DD5","hostname":"tools.cisco.com","tags":["Vendor Advisory","X Refsource CISCO"]}],"lineage":{"upstream":[],"downstream":[],"duplicates":[],"related":[]},"timeline":[{"kind":"published","date":"2021-03-24T20:15:33.955Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2024-11-08T23:32:25.328Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":29,"level":"medium","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-22T01:59:46.773Z","stale":false,"partial":false}}