Vulnerability in Cisco iOS Xe Software
CVE-2026-20311
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.
EPSS: 0.002 (5.3th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.3 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:N/I:N/A:H.
Affected products
- Cisco Ios Xe Software — versions 17.3.1, 17.3.1a, 17.3.2a
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-20311?
- CVE-2026-20311 is a medium-severity vulnerability in Cisco iOS Xe Software, classified under Buffer Over-read. CVSS score: 6.3/10. Published 2026-08-05.
- How severe is CVE-2026-20311?
- Medium severity. CVSS v3 base score is 6.3 out of 10.