Firepower Threat Defense
CVE-2021-1501
HIGH
Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Lifecycle Timeline
1DescriptionNVD
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.
AnalysisAI
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. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Technical ContextAI
This vulnerability is classified under CWE-613. 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. Affected products include: Cisco Firepower Threat Defense, Cisco Adaptive Security Appliance Software.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
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Same weakness CWE-613 – Insufficient Session Expiration
View allSame technique Denial Of Service
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External POC / Exploit Code
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