How severe is CVE-2021-1602?

CVE-2021-1602 has a CVSS 3.x base score of 8.2, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability high.

Is CVE-2021-1602 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-1602?

CVE-2021-1602 affects Cisco Small Business Rv Series Router Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-1602?

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

When was CVE-2021-1602 published?

CVE-2021-1602 was published on 2021-08-04 and last updated on 2026-06-17.

CVE-2021-1602

CVE-2021-1602 is a high-severity vulnerability in Cisco Small Business Rv Series Router Firmware with a CVSS 3.x base score of 8.2. 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-20.

Key facts

Severity: High (CVSS 3.x base score 8.2)
CVSS v2: 10.0
EPSS exploit prediction: 2% (79th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Small Business Rv Series Router Firmware
Published: 2021-08-04
Last modified: 2026-06-17

Description

A vulnerability in the web-based management interface of Cisco Small Business RV160, RV160W, RV260, RV260P, and RV260W VPN Routers could allow an unauthenticated, remote attacker to execute arbitrary commands on the underlying operating system of an affected device. This vulnerability is due to insufficient user input validation. An attacker could exploit this vulnerability by sending a crafted request to the web-based management interface. A successful exploit could allow the attacker to execute arbitrary commands on an affected device using root-level privileges. Due to the nature of the vulnerability, only commands without parameters can be executed.

Frequently asked questions

What is CVE-2021-1602?: A vulnerability in the web-based management interface of Cisco Small Business RV160, RV160W, RV260, RV260P, and RV260W VPN Routers could allow an unauthenticated, remote attacker to execute arbitrary commands on the underlying operating system of an affected device. This vulnerability is due to insufficient user input validation. An attacker could exploit this vulnerability by sending a crafted request to the web-based management interface. A successful exploit could allow the attacker to execute arbitrary commands on an affected device using root-level privileges. Due to the nature of the vulnerability, only commands without parameters can be executed.
How severe is CVE-2021-1602?: CVE-2021-1602 has a CVSS 3.x base score of 8.2, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability high.
Is CVE-2021-1602 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-1602?: CVE-2021-1602 affects Cisco Small Business Rv Series Router Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-1602?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-1602 published?: CVE-2021-1602 was published on 2021-08-04 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-rv-code-execution-9UVJr7k4

Affected products (1)

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

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