CVE-2026-20311
MediumCVSS 6.3Exploitation Probability (EPSS)
Low risk5th percentile - higher than 5% of all known CVEs
Summary
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 is due to insufficient error handling in the web-based management interface. An attacker could exploit this by authenticating with a malformed certificate, potentially causing the device to reload.
Risk Assessment
An attacker could cause device unavailability, potentially disrupting network operations and services.
Recommendation
Apply patches provided by Cisco and restrict access to the management interface to trusted users only.
Other vulnerabilities in Cisco IOS XE Software
See all- CVE-2026-20272Critical
As part of an internal security review in Cisco IOS XE Software, multiple vulnerabilities related to improper neutralization of special elements (CWE-74) were discovered. Hardened software releases addressing these issues have been issued.
- CVE-2026-20267Critical
As part of an internal security review in Cisco IOS XE Software, multiple vulnerabilities related to improper access control (CWE-284) were discovered. Hardened software releases addressing these issues have been issued.
- CVE-2017-12229Critical
A vulnerability in the web-based user interface (web UI) of Cisco IOS XE 3.1 through 16.5 allows an unauthenticated remote attacker to bypass authentication to the REST API. The issue is due to insufficient input validation for the REST API.
- CVE-2026-20308Medium
A vulnerability in the web-based management interface of Cisco IOS XE Software allows an authenticated remote attacker with low privileges to perform a DoS attack. The issue is due to insufficient input validation, and exploitation can make the interface unresponsive.
- CVE-2026-20273High
A vulnerability in Cisco IOS XE Software related to improper input validation (CWE-20), discovered during an internal security review. It is addressed in a software hardening release.
- CVE-2026-20271High
A vulnerability in Cisco IOS XE Software related to insufficient control flow management (CWE-691), discovered during an internal security review. It is addressed in software hardening releases.
- CVE-2026-20270High
A vulnerability in Cisco IOS XE Software related to incorrect calculation issues (CWE-682), discovered during an internal security review. It is addressed in software hardening releases.
- CVE-2026-20269High
A vulnerability in Cisco IOS XE Software related to improper control of a resource through its lifetime (CWE-664), discovered during an internal security review. It is addressed in software hardening releases.
- CVE-2026-20268High
A vulnerability in Cisco IOS XE Software related to improper restriction of operations within the bounds of a memory buffer (CWE-119), discovered during an internal security review. It is addressed in software hardening releases.
- CVE-2026-20263High
A vulnerability in the BEEP feature of Cisco IOS XE Software allows an unauthenticated remote attacker to cause a denial of service (DoS) by sending a specific BEEP SOAP request. The issue is due to improper handling during parsing.
Original NVD description (English source)
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.