How severe is CVE-2021-1609?

CVE-2021-1609 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-1609 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 10% (95th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-1609?

CVE-2021-1609 affects Cisco Small Business Rv Series Router Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-1609?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-1609 published?

CVE-2021-1609 was published on 2021-08-04 and last updated on 2026-06-17.

CVE-2021-1609

CVE-2021-1609 is a critical-severity vulnerability in Cisco Small Business Rv Series Router Firmware with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-121.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 10% (95th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-121
Affected product: Cisco Small Business Rv Series Router Firmware
Published: 2021-08-04
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2021-1609?: 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.
How severe is CVE-2021-1609?: CVE-2021-1609 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-1609 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 10% (95th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-1609?: CVE-2021-1609 affects Cisco Small Business Rv Series Router Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-1609?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-1609 published?: CVE-2021-1609 was published on 2021-08-04 and last updated on 2026-06-17.

References

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

Affected products (1)

cpe:2.3:o:cisco:small_business_rv_series_router_firmware:*:*:*:*:*:*:*:*

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