CVE-2021-1403 - CVE House
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Status published High CVE-2021-1403

Cisco IOS XE Software Web UI Cross-Site WebSocket Hijacking Vulnerability

Vulnerability Description

A vulnerability in the web UI feature of Cisco IOS XE Software could allow an unauthenticated, remote attacker to conduct a cross-site WebSocket hijacking (CSWSH) attack and cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient HTTP protections in the web UI on an affected device. An attacker could exploit this vulnerability by persuading an authenticated user of the web UI to follow a crafted link. A successful exploit could allow the attacker to corrupt memory on the affected device, forcing it to reload and causing a DoS condition.

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: March 24th, 2021
Last Modified: November 8th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:H

Weaknesses (CWE)

CWE-345

MITRE ATT&CK TTPs

T1557 Adversary-in-the-Middle
Credential Access
T1071 Application Layer Protocol
Command and Control
T1552 Unsecured Credentials
Credential Access
T1190 Exploit Public-Facing Application
Initial Access
T1041 Exfiltration Over C2 Channel
Exfiltration