CVE-2026-20156: Buffer Overflow (CVSS 8.1)

Description

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco RoomOS engineering team has conducted a comprehensive internal security review. This review resulted in a software hardening release that addresses multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-20156 are related to improper restriction of operations within the bounds of a memory buffer that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-119.

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CVSS v3.1 Score

8.1

HIGH

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

EPSS — Exploit Prediction

0.0023

Probability of exploitation

0.14%

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-119 Buffer Overflow

References

Other References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-roomos-AqNMbEq

Frequently Asked Questions

What is CVE-2026-20156? +

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco RoomOS engineering team has conducted a comprehensive internal security review. This review resulted in a software hardening release that addresses multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-20156 are related to improper restriction of operations within the bounds of a memory buffer that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-119. It has a CVSS v3.1 base score of 8.1 (HIGH).

How severe is CVE-2026-20156? +

CVE-2026-20156 has a CVSS v3.1 score of 8.1 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0023, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-20156? +

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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