CVE-2026-20177: DoS (CVSS 5.3)

Description

A vulnerability in the handling of management plane packets by Cisco Industrial Ethernet (IE) 1000 Series Switches could allow an unauthenticated, remote attacker to cause the device manager, SSH, or API to become inaccessible.This vulnerability is due to insufficient protection against management plane flooding attacks. An attacker could exploit this vulnerability by sending a high rate of ICMP, SSH, or HTTP traffic to an affected device. A successful exploit could allow the attacker to cause the CPU of the device to increase, resulting in a denial of service (DoS) condition on the device manager web GUI, SSH, or API. Data traffic through the device is not affected.

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CVSS v3.1 Score

5.3

MEDIUM

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

EPSS — Exploit Prediction

0.0039

Probability of exploitation

0.33%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-770 CWE-770

References

Other References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ie1k-uxq86Lnx

Frequently Asked Questions

What is CVE-2026-20177? +

A vulnerability in the handling of management plane packets by Cisco Industrial Ethernet (IE) 1000 Series Switches could allow an unauthenticated, remote attacker to cause the device manager, SSH, or API to become inaccessible.This vulnerability is due to insufficient protection against management plane flooding attacks. An attacker could exploit this vulnerability by sending a high rate of ICMP, SSH, or HTTP traffic to an affected device. A successful exploit could allow the attacker to cause the CPU of the device to increase, resulting in a denial of service (DoS) condition on the device manager web GUI, SSH, or API. Data traffic through the device is not affected. It has a CVSS v3.1 base score of 5.3 (MEDIUM).

How severe is CVE-2026-20177? +

CVE-2026-20177 has a CVSS v3.1 score of 5.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0039, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-20177? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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