AI and data stack advisories

Severe, 6 weeks1496Projects326

1496 severe, 6 weeks · 326 projects

CiscoCVE-2026-20273

Cisco IOS XE Software: improper input validation

Cisco

CVE-2026-20273 · Published Aug 5, 2026 · updated Oct 3, 2026

High8.6
No fix yet
Cisco advisory

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco IOS XE Software 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-2026-20273 are related to improper input validation issues that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-20.

Affected versions

PackageAffectedFixed in
Cisco IOS XE Software
Product
<= 17.2.1aNo fix yet
<= 16.12.1yNo fix yet
<= 16.12.3sNo fix yet
<= 16.7.1bNo fix yet
Details and references
CVSS 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Severity from
the vendor (its own CVE record or advisory)
Weakness
CWE-20

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