How severe is CVE-2020-3358?

CVE-2020-3358 has a CVSS 3.x base score of 8.6, 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 none, and availability high.

Is CVE-2020-3358 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-3358?

CVE-2020-3358 primarily affects Cisco Rv340 Dual Wan Gigabit Vpn Router Firmware. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-3358?

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-2020-3358 published?

CVE-2020-3358 was published on 2020-07-16 and last updated on 2026-06-17.

CVE-2020-3358

CVE-2020-3358 is a high-severity vulnerability in Cisco Rv340 Dual Wan Gigabit Vpn Router Firmware with a CVSS 3.x base score of 8.6. 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 8.6)
CVSS v2: 7.8
EPSS exploit prediction: 1% (69th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Rv340 Dual Wan Gigabit Vpn Router Firmware
Published: 2020-07-16
Last modified: 2026-06-17

Description

A vulnerability in the Secure Sockets Layer (SSL) VPN feature for Cisco Small Business RV VPN Routers could allow an unauthenticated, remote attacker to cause the device to unexpectedly restart, causing a denial of service (DoS) condition. The vulnerability is due to a lack of proper input validation of HTTP requests. An attacker could exploit this vulnerability by sending a crafted HTTP request over an SSL connection to the targeted device. A successful exploit could allow the attacker to cause a reload, resulting in a DoS condition.

Frequently asked questions

What is CVE-2020-3358?: A vulnerability in the Secure Sockets Layer (SSL) VPN feature for Cisco Small Business RV VPN Routers could allow an unauthenticated, remote attacker to cause the device to unexpectedly restart, causing a denial of service (DoS) condition. The vulnerability is due to a lack of proper input validation of HTTP requests. An attacker could exploit this vulnerability by sending a crafted HTTP request over an SSL connection to the targeted device. A successful exploit could allow the attacker to cause a reload, resulting in a DoS condition.
How severe is CVE-2020-3358?: CVE-2020-3358 has a CVSS 3.x base score of 8.6, 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 none, and availability high.
Is CVE-2020-3358 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3358?: CVE-2020-3358 primarily affects Cisco Rv340 Dual Wan Gigabit Vpn Router Firmware. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-3358?: 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-2020-3358 published?: CVE-2020-3358 was published on 2020-07-16 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sb-dos-ZN5GvNH7

Affected products (4)

cpe:2.3:o:cisco:rv340_dual_wan_gigabit_vpn_router_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:rv340w_dual_wan_gigabit_wireless-ac_vpn_router_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:rv345_dual_wan_gigabit_vpn_router_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:cisco:rv345p_dual_wan_gigabit_poe_vpn_router_firmware:*:*:*:*:*:*:*:*

More vulnerabilities in Cisco Rv340 Dual Wan Gigabit Vpn Router Firmware

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