CVE Vulnerabilities

CVE-2021-1422

Reachable Assertion

Published: Jul 16, 2021 | Modified: Nov 07, 2023
CVSS 3.x
7.7
HIGH
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
CVSS 2.x
6.8 MEDIUM
AV:N/AC:L/Au:S/C:N/I:N/A:C
RedHat/V2
RedHat/V3
Ubuntu

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.

Weakness

The product contains an assert() or similar statement that can be triggered by an attacker, which leads to an application exit or other behavior that is more severe than necessary.

Affected Software

Name Vendor Start Version End Version
Adaptive_security_appliance_software Cisco 9.16.1 (including) 9.16.1 (including)
Firepower_threat_defense Cisco 7.0.0.0 (including) 7.0.0.0 (including)

Extended Description

While assertion is good for catching logic errors and reducing the chances of reaching more serious vulnerability conditions, it can still lead to a denial of service. For example, if a server handles multiple simultaneous connections, and an assert() occurs in one single connection that causes all other connections to be dropped, this is a reachable assertion that leads to a denial of service.

Potential Mitigations

References