← Vulnerability feed

Vulnerability record · CVE-2021-1609 · published 4 August 2021

CVE-2021-1609: Cisco small business rv series router firmware stack-based buffer overflow vulnerability

Cisco · Small Business Rv Series Router Firmware

Multiple vulnerabilities in the web-based management interface of the Cisco Small Business RV340, RV340W, RV345, and RV345P Dual WAN Gigabit VPN Routers could allow an attacker to do the following: Execute arbitrary code Cause a denial of service (DoS) condition Execute arbitrary commands For more information about these vulnerabilities, see the Details section of this advisory.

9.8 CVSS 3.1 Critical EPSS 9.7% · top 4.7% CWE-121 · Stack-based buffer overflow
9.8CVSS 3.1 base score, v2 10.0
9.7%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
2References
17 Jun 2026Last modified by NVD

Description

Multiple vulnerabilities in the web-based management interface of the Cisco Small Business RV340, RV340W, RV345, and RV345P Dual WAN Gigabit VPN Routers could allow an attacker to do the following: Execute arbitrary code Cause a denial of service (DoS) condition Execute arbitrary commands For more information about these vulnerabilities, see the Details section of this advisory.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-rv340-cmdinj-rcedos-pY8J3qfy Vendor Advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-rv340-cmdinj-rcedos-pY8J3qfy Vendor Advisory

Track CVE-2021-1609 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.8CVE-2021-1602Cisco small business rv series router firmware os command injection vulnerabilityA vulnerability in the web-based management interface of Cisco Small Business RV160, RV160W, RV260, RV260P, and RV260W VPN Routers could allow an una…EPSS 2.0%8.8CVE-2024-20381Cisco ios xr improper authorization vulnerabilityA vulnerability in the JSON-RPC API feature in Cisco Crosswork Network Services Orchestrator (NSO) and ConfD that is used by the web-based management…EPSS 0.58%8.8CVE-2021-1610Cisco small business rv series router firmware stack-based buffer overflow vulnerabilityMultiple vulnerabilities in the web-based management interface of the Cisco Small Business RV340, RV340W, RV345, and RV345P Dual WAN Gigabit VPN Rout…EPSS 9.1%5.8CVE-2017-6620Cisco small business rv series router firmware permissions and access controls vulnerabilityA vulnerability in the remote management access control list (ACL) feature of the Cisco CVR100W Wireless-N VPN Router could allow an unauthenticated,…EPSS 1.6%8.8CVE-2026-7273Zyxel gs1900-8 firmware stack-based buffer overflow vulnerabilityA stack-based buffer overflow vulnerability in the CGI program of Zyxel GS1900-48HPv2 firmware versions through 2.90(ABTQ.1)C0 could allow a LAN-base…KEVEPSS 2.5%8.1CVE-2021-27137DD-WRT UPnP M-SEARCH stack buffer overflowDD-WRT before 45724 contains an unsafe strcpy in the UPnP SSDP handling code (ssdp_msearch), reachable via an M-SEARCH request, that overflows a fixe…KEVEPSS 4.0%analysed9.3CVE-2025-53521F5 BIG-IP APM stack buffer overflow allows remote code executionA stack-based buffer overflow (CWE-121) exists in F5 BIG-IP Access Policy Manager when an APM access policy is configured on a virtual server. Specif…KEVEPSS 2.3%analysed8.8CVE-2008-0015Microsoft DirectShow Video ActiveX Control Stack Buffer OverflowA stack-based buffer overflow in the CComVariant::ReadFromStream function in the Active Template Library (ATL) is reachable through the MPEG2TuneRequ…KEVEPSS 77%analysed

Source: NIST National Vulnerability Database (record CVE-2021-1609), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.