CVE-2020-3426

CVE-2020-3426 is a high-severity vulnerability in Cisco Ios with a CVSS 3.x base score of 7.5. 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

Description

A vulnerability in the implementation of the Low Power, Wide Area (LPWA) subsystem of Cisco IOS Software for Cisco 800 Series Industrial Integrated Services Routers (Industrial ISRs) and Cisco 1000 Series Connected Grid Routers (CGR1000) could allow an unauthenticated, remote attacker to gain unauthorized read access to sensitive data or cause a denial of service (DoS) condition. The vulnerability is due to a lack of input and validation checking mechanisms for virtual-LPWA (VLPWA) protocol modem messages. An attacker could exploit this vulnerability by supplying crafted packets to an affected device. A successful exploit could allow the attacker to gain unauthorized read access to sensitive data or cause the VLPWA interface of the affected device to shut down, resulting in DoS condition.

Frequently asked questions

What is CVE-2020-3426?
A vulnerability in the implementation of the Low Power, Wide Area (LPWA) subsystem of Cisco IOS Software for Cisco 800 Series Industrial Integrated Services Routers (Industrial ISRs) and Cisco 1000 Series Connected Grid Routers (CGR1000) could allow an unauthenticated, remote attacker to gain unauthorized read access to sensitive data or cause a denial of service (DoS) condition. The vulnerability is due to a lack of input and validation checking mechanisms for virtual-LPWA (VLPWA) protocol modem messages. An attacker could exploit this vulnerability by supplying crafted packets to an affected device. A successful exploit could allow the attacker to gain unauthorized read access to sensitive data or cause the VLPWA interface of the affected device to shut down, resulting in DoS condition.
How severe is CVE-2020-3426?
CVE-2020-3426 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2020-3426 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3426?
CVE-2020-3426 affects Cisco Ios. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-3426?
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-2020-3426 published?
CVE-2020-3426 was published on 2020-09-24 and last updated on 2026-06-17.

References

Affected products (1)

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