CVE-2026-20274CWE-664

CVE-2026-20274

Critical · published September 2, 2026

CVSS v3.1
9.8
EPSS
1%
Percentile
49.8
In the wild
Unconfirmed
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.

The record
Technical detail
CVSS v3.1
9.8 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00672 · 49.8th percentile
Weakness
CWE-664 · Improper Control of a Resource Through its Lifetime
Published
2026-09-02T21:17Z
References (1)
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-hardening-iosxr-qg64NcM · [email protected]
EPSS history
Timeline
  • 04 SEP 03:39Z
    EPSS moved — → 1%
    epss
  • 02 SEP 16:13Z
    Cisco IOS XR Software Security Hardening Release: September 2026
    cvelistv5