CVE-2021-34699 - CVE House
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Status published High CVE-2021-34699

Cisco IOS and IOS XE Software TrustSec CLI Parser Denial of Service Vulnerability

Vulnerability Description

A vulnerability in the TrustSec CLI parser of Cisco IOS and Cisco IOS XE Software could allow an authenticated, remote attacker to cause an affected device to reload. This vulnerability is due to an improper interaction between the web UI and the CLI parser. An attacker could exploit this vulnerability by requesting a particular CLI command to be run through the web UI. A successful exploit could allow the attacker to cause the device to reload, resulting in a denial of service (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
Vulnerable Versions:
Unknown

Timeline

Official Publish: September 23rd, 2021
Last Modified: November 18th, 2024
Added to House: July 21st, 2026

CVSS Vectors

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

Weaknesses (CWE)

CWE-435

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.