CVE-2026-20311
Cisco IOS XE Software Web UI Denial of Service Vulnerability
CVSS Score
6.3
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-126 |
| Vendor | cisco |
| Product | cisco ios xe software |
| Ecosystems | |
| Industries | NetworkingTelecommunications |
| Published | Aug 5, 2026 |
| Last Updated | Aug 5, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:N/A:H Attack Vector
Network
Attack Complexity
High
Privileges Required
Low
User Interaction
None
Scope
Changed
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
Cisco / Cisco IOS XE Software
17.3.1 17.3.1a 17.3.2a 17.3.1w 17.3.2 17.4.1 17.4.1a 17.3.1x 17.3.3 17.5.1 17.4.1b 17.3.1z 17.4.2 17.3.3a 17.3.5 17.3.4 17.5.1a 17.6.1 17.3.4a 17.6.1a 17.7.1 17.6.1x 17.6.2 17.3.4c 17.4.2a 17.3.4b 17.7.1a 17.8.1a 17.6.3a 17.6.3 17.7.2 17.7.1b 17.9.1w 17.3.5a 17.6.1z 17.8.1 17.9.1 17.6.4 17.3.5b 17.9.1a 17.3.6 17.10.1 17.6.1z1 17.10.1a 17.9.2 17.6.5 17.9.1x 17.9.1y 17.3.7 17.9.2a 17.9.3 17.11.1 17.10.1b 17.6.6 17.9.1x1 17.11.1a 17.9.3a 17.12.1 17.3.8 17.9.4 17.12.1w 17.9.1y1 17.12.1a 17.9.5 17.13.1 17.12.1x 17.12.2 17.14.1 17.9.4a 17.3.8a 17.6.6a 17.6.5a 17.6.7 17.15.1 17.13.1a 17.12.2a 17.12.3 17.12.1y 17.12.1z 17.9.5a 17.14.1a 17.9.5b 17.6.8 17.12.4 17.9.6 17.17.1 17.16.1 17.15.1w 17.12.3a 17.9.5c 17.15.1a 17.12.1z1 17.15.2 17.15.1b 17.9.5d 17.15.1x 17.9.6a 17.12.1z2 17.6.8a 17.16.1a 17.15.3 17.9.7 17.12.5 17.15.1y 17.9.5e 17.12.4a 17.15.2a 17.15.2c 17.15.2b 17.12.1z3 17.9.5f 17.12.4b 17.12.5a 17.18.1 17.12.6 17.12.1z4 17.9.8 17.9.7a 17.15.3a 17.15.4 17.12.5b 17.15.3b 17.18.1z 17.9.7b 17.12.5c 26.1.1 17.18.1a 17.15.4a 17.18.2 17.18.1w 17.15.4b 17.12.6a 17.12.7 17.15.4c 17.9.9 17.12.5d 17.15.4s1 17.15.5 17.12.1z5 17.18.1x 17.12.1z6 17.15.4d 17.12.6b 17.4.1c 17.15.5a 17.18.1y 17.12.7a 17.18.3 17.12.7b 17.18.3a 26.1.1a 26.2.1ea