// For flags

CVE-2021-34787

Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Identity-Based Rule Bypass Vulnerability

Severity Score

5.3
*CVSS v3.1

Exploit Likelihood

< 1%
*EPSS

Affected Versions

25
*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Attend
*SSVC
Descriptions

A vulnerability in the identity-based firewall (IDFW) rule processing feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass security protections. This vulnerability is due to improper handling of network requests by affected devices configured to use object group search. An attacker could exploit this vulnerability by sending a specially crafted network request to an affected device. A successful exploit could allow the attacker to bypass access control list (ACL) rules on the device, bypass security protections, and send network traffic to unauthorized hosts.

Una vulnerabilidad en la funcionalidad de procesamiento de reglas del firewall basado en la identidad (IDFW) del software Cisco Adaptive Security Appliance (ASA) y del software Cisco Firepower Threat Defense (FTD) podría permitir a un atacante remoto no autenticado omitir las protecciones de seguridad. Esta vulnerabilidad es debido al manejo inapropiado de las peticiones de red por parte de los dispositivos afectados configurados para usar la búsqueda de grupos de objetos. Un atacante podría aprovechar esta vulnerabilidad mediante el envío de una petición de red especialmente diseñada a un dispositivo afectado. Una explotación con éxito podría permitir al atacante omitir las reglas de la lista de control de acceso (ACL) en el dispositivo, omitir las protecciones de seguridad y enviar tráfico de red a hosts no autorizados

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
None
Attack Vector
Network
Attack Complexity
Medium
Authentication
None
Confidentiality
None
Integrity
Partial
Availability
None
* Common Vulnerability Scoring System
SSVC
  • Decision:Attend
Exploitation
None
Automatable
Yes
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2021-06-15 CVE Reserved
  • 2021-10-27 CVE Published
  • 2024-11-07 CVE Updated
  • 2025-03-30 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-183: Permissive List of Allowed Inputs
  • CWE-755: Improper Handling of Exceptional Conditions
CAPEC
Affected Vendors, Products, and Versions (25)