CVE-2026-20311

Cisco IOS XE Software Web UI Denial of Service Vulnerability

Published Aug 5, 2026 CVSS 3.1 · 6.3 Medium EPSS < 1% KEV · Not listed
Description
A vulnerability in the web-based management interface of Cisco IOS XE Software could allow an authenticated, remote attacker with low privileges to cause a denial of service (DoS) condition on an affected device.

This vulnerability is due to insufficient error handling in the web-based management interface. An attacker could exploit this vulnerability by authenticating with a malformed certificate. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Cisco
Cisco ios Xe Software
Vendors & Products Cisco
Cisco ios Xe Software
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description A vulnerability in the web-based management interface of Cisco IOS XE Software could allow an authenticated, remote attacker with low privileges to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient error handling in the web-based management interface. An attacker could exploit this vulnerability by authenticating with a malformed certificate. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.
Title Cisco IOS XE Software Web UI Denial of Service Vulnerability
Weaknesses CWE-126
References
Metrics cvssV3_1

{'score': 6.3, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:N/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
cisco
Published
Updated
Aug 5, 2026, 5:45 PM
Reserved
Oct 8, 2025, 11:59 AM
Status
Awaiting Analysis
Published
Aug 5, 2026, 5:16 PM
Modified
Oct 23, 2026, 9:10 PM