How severe is CVE-2026-20231?

CVE-2026-20231 has a CVSS 3.x base score of 9.9, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-20231 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2026-20231?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2026-20231 published?

CVE-2026-20231 was published on 2026-08-19 and last updated on 2026-08-20.

CVE-2026-20231

CVE-2026-20231 is a critical-severity vulnerability with a CVSS 3.x base score of 9.9. 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-74.

Key facts

Severity: Critical (CVSS 3.x base score 9.9)
EPSS exploit prediction: 0% (35th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-74
Published: 2026-08-19
Last modified: 2026-08-20

Description

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Secure Workload 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-2026-20231 are related to improper neutralization of special elements issues that are grouped under the Common Weakness Enumeration (CWE) CWE-74.

Frequently asked questions

What is CVE-2026-20231?: As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Secure Workload 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-2026-20231 are related to improper neutralization of special elements issues that are grouped under the Common Weakness Enumeration (CWE) CWE-74.
How severe is CVE-2026-20231?: CVE-2026-20231 has a CVSS 3.x base score of 9.9, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-20231 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2026-20231?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2026-20231 published?: CVE-2026-20231 was published on 2026-08-19 and last updated on 2026-08-20.

References

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