CVE-2021-1501 - CVE House
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Status published High CVE-2021-1501

Cisco Adaptive Security Appliance Software and Cisco Firepower Threat Defense Software SIP Denial of Service Vulnerability

Vulnerability Description

A vulnerability in the SIP inspection engine of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a crash and reload of an affected device, resulting in a denial of service (DoS) condition.The vulnerability is due to a crash that occurs during a hash lookup for a SIP pinhole connection. An attacker could exploit this vulnerability by sending crafted SIP traffic through an affected device. A successful exploit could allow the attacker to cause a crash and reload of the affected device.

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 Adaptive Security Appliance (ASA) Software
Vulnerable Versions:
Unknown

Timeline

Official Publish: April 29th, 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:N/S:C/C:N/I:N/A:H

Weaknesses (CWE)

CWE-613

MITRE ATT&CK TTPs

T1539 Steal Web Session Cookie
Credential Access
T1078 Valid Accounts
Persistence
T1550 Use Alternate Authentication Material
Defense Evasion
T1021 Remote Services
Lateral Movement
T1562 Impair Defenses
Defense Evasion