CVE-2026-20274

What it is

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco IOS XR Software engineering team has conducted a comprehensive internal security review. This review resulted in a software hardening releases that address multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-20274 are related to improper resource control issues that are grouped under the Common Weakness Enumeration (CWE) CWE-664.

At a glance

Exploitability

Can be exploited over the network without logging in. High risk of data exposure, data tampering, service disruption.

Exploit odds

0.5% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-09-02 17:17 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-09-17 18:03 UTC Last updatedMost recent change to the record

Details

Published

2026-09-02 17:17 UTC

Last modified

2026-09-17 18:03 UTC

Exploit probability

0.5% · EPSS, next 30 days

Weakness

CWE-664

Record status

Analyzed

Affected

• Cisco iOS Xr 6.5.25
• Cisco iOS Xr 6.5.26
• Cisco iOS Xr 6.5.28
• Cisco iOS Xr 6.5.29
• Cisco iOS Xr 6.5.31
• Cisco iOS Xr 6.5.32
• Cisco iOS Xr 6.5.33
• Cisco iOS Xr 6.5.35

Attack profile CVSS 3.1 · 9.8

Attack vector

Network

Complexity

Low

Privileges needed

None

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High