{"cve":"CVE-2021-34730","nvd":{"published":"2021-08-18T20:15:07.447","modified":"2026-06-17T03:56:26.723","status":"Modified","description":"A vulnerability in the Universal Plug-and-Play (UPnP) service of Cisco Small Business RV110W, RV130, RV130W, and RV215W Routers could allow an unauthenticated, remote attacker to execute arbitrary code or cause an affected device to restart unexpectedly, resulting in a denial of service (DoS) condition. This vulnerability is due to improper validation of incoming UPnP traffic. An attacker could exploit this vulnerability by sending a crafted UPnP request to an affected device. A successful exploit could allow the attacker to execute arbitrary code as the root user on the underlying operating system or cause the device to reload, resulting in a DoS condition. Cisco has not released software updates that address this vulnerability.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":9.8},"cwes":["CWE-787","CWE-121"],"references":["https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cisco-sb-rv-overflow-htpymMB5","https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-cisco-sb-rv-overflow-htpymMB5"],"products":["cisco:application_extension_platform","cisco:rv110w_wireless-n_vpn_firewall_firmware","cisco:rv130_vpn_router_firmware","cisco:rv130w_wireless-n_multifunction_vpn_router_firmware","cisco:rv215w_wireless-n_vpn_router_firmware"],"source":"nvd","synced_at":"2026-10-19T21:21:57.125947417+00:00"},"epss":{"cve":"CVE-2021-34730","score":0.185,"percentile":0.97247,"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."]}