CVE-2020-3516 - CVE House
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Status published Medium CVE-2020-3516

Cisco IOS XE Software Web UI Improper Input Validation Vulnerability

Vulnerability Description

A vulnerability in the web server authentication of Cisco IOS XE Software could allow an authenticated, remote attacker to crash the web server on the device. The vulnerability is due to insufficient input validation during authentication. An attacker could exploit this vulnerability by entering unexpected characters during a valid authentication. A successful exploit could allow the attacker to crash the web server on the device, which must be manually recovered by disabling and re-enabling the web server.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

Cisco IOS XE Software
Vulnerable Versions:
Unknown

Timeline

Official Publish: September 24th, 2020
Last Modified: November 13th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

Weaknesses (CWE)

CWE-20

MITRE ATT&CK TTPs

T1190 Exploit Public-Facing Application
Initial Access
T1059 Command and Scripting Interpreter
Execution
T1068 Exploitation for Privilege Escalation
Privilege Escalation
T1213 Data from Information Repositories
Collection
T1565.002 Stored Data Manipulation
Impact