CVE Vulnerabilities

CVE-2021-34792

Missing Release of Memory after Effective Lifetime

Published: Oct 27, 2021 | Modified: Nov 07, 2023
CVSS 3.x
7.5
HIGH
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS 2.x
7.8 HIGH
AV:N/AC:L/Au:N/C:N/I:N/A:C
RedHat/V2
RedHat/V3
Ubuntu

A vulnerability in the memory management of Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper resource management when connection rates are high. An attacker could exploit this vulnerability by opening a significant number of connections on an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.

Weakness

The product does not sufficiently track and release allocated memory after it has been used, which slowly consumes remaining memory.

Affected Software

Name Vendor Start Version End Version
Firepower_threat_defense Cisco 6.4.0 (including) 6.4.0.13 (excluding)
Firepower_threat_defense Cisco 6.6.0 (including) 6.6.5 (excluding)
Firepower_threat_defense Cisco 6.7.0 (including) 6.7.0.3 (excluding)
Firepower_threat_defense Cisco 7.0.0 (including) 7.0.1 (excluding)
Adaptive_security_appliance_software Cisco 9.8.0 (including) 9.8.4.40 (excluding)
Adaptive_security_appliance_software Cisco 9.12.0 (including) 9.12.4.29 (excluding)
Adaptive_security_appliance_software Cisco 9.14.0 (including) 9.14.3.9 (excluding)
Adaptive_security_appliance_software Cisco 9.15.0 (including) 9.15.1.17 (excluding)
Adaptive_security_appliance_software Cisco 9.16.0 (including) 9.16.2.3 (excluding)

Potential Mitigations

  • Choose a language or tool that provides automatic memory management, or makes manual memory management less error-prone.
  • For example, glibc in Linux provides protection against free of invalid pointers.
  • When using Xcode to target OS X or iOS, enable automatic reference counting (ARC) [REF-391].
  • To help correctly and consistently manage memory when programming in C++, consider using a smart pointer class such as std::auto_ptr (defined by ISO/IEC ISO/IEC 14882:2003), std::shared_ptr and std::unique_ptr (specified by an upcoming revision of the C++ standard, informally referred to as C++ 1x), or equivalent solutions such as Boost.

References