CVE-2020-3257

Name: CVE-2020-3257
Creator: NVD / NIST
Published: 2020-06-03T18:15:21.84+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.1/10EPSS 0.70%

Last modified Jun 17, 2026

CVE-2020-3257 is a high-severity vulnerability rated 8.1/10 on the CVSS scale. Multiple vulnerabilities in the Cisco IOx application environment of Cisco 809 and 829 Industrial Integrated Services Routers (Industrial ISRs) and Cisco 1000 Series Connected Grid Routers (CGR1000) that are running Cisco IOS Software could allow an attacker to cause a denial of service (DoS) condition or execute arbitrary code with elevated privileges on an affected device. For more information about these vulnerabilities, see the Details section of this advisory.. EPSS estimates a 0.70% chance of exploitation in the next 30 days.

Description

Multiple vulnerabilities in the Cisco IOx application environment of Cisco 809 and 829 Industrial Integrated Services Routers (Industrial ISRs) and Cisco 1000 Series Connected Grid Routers (CGR1000) that are running Cisco IOS Software could allow an attacker to cause a denial of service (DoS) condition or execute arbitrary code with elevated privileges on an affected device. For more information about these vulnerabilities, see the Details section of this advisory.

Metrics

CVSS 3.1

8.1/10

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

EPSS Probability

0.70%

48.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Cisco	Ios	15.8\(3.0z\)m1
Cisco	Ios	15.9

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-iot-gos-vuln-s9qS8kYLPatch, Vendor Advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ios-iot-gos-vuln-s9qS8kYLPatch, Vendor Advisory

Timeline

Published: Jun 3, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-3257?

How severe is CVE-2020-3257?

CVE-2020-3257 has a CVSS score of 8.1/10 (HIGH severity). The EPSS model estimates a 0.70% probability of exploitation in the next 30 days.

How do I fix CVE-2020-3257?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-3257?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST