{"cve":"CVE-2021-1531","nvd":{"published":"2021-05-22T07:15:07.350","modified":"2026-06-17T03:31:59.777","status":"Modified","description":"A vulnerability in the web UI of Cisco Modeling Labs could allow an authenticated, remote attacker to execute arbitrary commands with the privileges of the web application on the underlying operating system of an affected Cisco Modeling Labs server. This vulnerability is due to insufficient validation of user-supplied input to the web UI. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected server. A successful exploit could allow the attacker to execute arbitrary commands with the privileges of the web application, virl2, on the underlying operating system of the affected server. To exploit this vulnerability, the attacker must have valid user credentials on the web UI.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":8.8},"cwes":["CWE-88"],"references":["http://packetstormsecurity.com/files/163265/Cisco-Modeling-Labs-2.1.1-b19-Remote-Command-Execution.html","https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cml-cmd-inject-N4VYeQXB","http://packetstormsecurity.com/files/163265/Cisco-Modeling-Labs-2.1.1-b19-Remote-Command-Execution.html","https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cml-cmd-inject-N4VYeQXB"],"products":["cisco:modeling_labs"],"source":"nvd","synced_at":"2026-10-19T21:18:09.669877188+00:00"},"epss":{"cve":"CVE-2021-1531","score":0.30492,"percentile":0.98237,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}