Adaptive Security Appliance Software
CVE-2021-1422
HIGH
Severity by source
AV:N/AC:L/PR:L/UI:N/S:C/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:L/UI:N/S:C/C:N/I:N/A:H
Lifecycle Timeline
1DescriptionNVD
A vulnerability in the software cryptography module of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, remote attacker or an unauthenticated attacker in a man-in-the-middle position to cause an unexpected reload of the device that results in a denial of service (DoS) condition. The vulnerability is due to a logic error in how the software cryptography module handles specific types of decryption errors. An attacker could exploit this vulnerability by sending malicious packets over an established IPsec connection. A successful exploit could cause the device to crash, forcing it to reload. Important: Successful exploitation of this vulnerability would not cause a compromise of any encrypted data. Note: This vulnerability affects only Cisco ASA Software Release 9.16.1 and Cisco FTD Software Release 7.0.0.
AnalysisAI
A vulnerability in the software cryptography module of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, remote attacker. Rated high severity (CVSS 7.7), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Technical ContextAI
This vulnerability is classified under CWE-617. A vulnerability in the software cryptography module of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, remote attacker or an unauthenticated attacker in a man-in-the-middle position to cause an unexpected reload of the device that results in a denial of service (DoS) condition. The vulnerability is due to a logic error in how the software cryptography module handles specific types of decryption errors. An attacker could exploit this vulnerability by sending malicious packets over an established IPsec connection. A successful exploit could cause the device to crash, forcing it to reload. Important: Successful exploitation of this vulnerability would not cause a compromise of any encrypted data. Note: This vulnerability affects only Cisco ASA Software Release 9.16.1 and Cisco FTD Software Release 7.0.0. Affected products include: Cisco Adaptive Security Appliance Software, Cisco Firepower Threat Defense.
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.
Buffer overflow in the IKEv1 and IKEv2 implementations in Cisco ASA Software before 8.4(7.30), 8.7 before 8.7(1.18), 9.0
Update: On November 5, 2025, Cisco became aware of a new attack variant against devices running Cisco Secure ASA Softwar
Cisco Adaptive Security Appliance (ASA) Software 8.x before 8.2(5.48), 8.3 before 8.3(2.40), 8.4 before 8.4(7.9), 8.6 be
A vulnerability in Common Internet Filesystem (CIFS) code in the Clientless SSL VPN functionality of Cisco ASA Software,
A vulnerability in the Secure Sockets Layer (SSL) VPN functionality of the Cisco Adaptive Security Appliance (ASA) Softw
A vulnerability in the web services interface of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Th
A vulnerability in the web services interface for remote access VPN features of Cisco Adaptive Security Appliance (ASA)
A vulnerability in the authorization subsystem of Cisco Adaptive Security Appliance (ASA) Software could allow an authen
A vulnerability in the web services interface of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Th
A vulnerability in the web interface of the Cisco Adaptive Security Appliance (ASA) could allow an unauthenticated, remo
The encryption-processing feature in Cisco libSRTP before 1.5.3 allows remote attackers to cause a denial of service via
Stack-based buffer overflow in the DCERPC inspection engine on Cisco Adaptive Security Appliances (ASA) 5500 series devi
Same weakness CWE-617 – Reachable Assertion
View allSame technique Denial Of Service
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External POC / Exploit Code
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