CVE-2026-20028

A vulnerability in the network driver of Cisco Terminal Service (TS) Agent could allow an authenticated, remote attacker to bypass firewall rules that are associated with the account of the attacker. This vulnerability is due to an incorrect mapping of network connections to user accounts. An attacker with at least user-level credentials could exploit this vulnerability by sending crafted network traffic to an affected device. A successful exploit could allow the attacker to inherit the firewall rules associated with a different user in the system.

CVSS v3 5.0 MEDIUM

5.0^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.1 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ts-agent-fw-bypass-MYBTMrev

Configurations

No configuration.

History

23 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) Una vulnerabilidad en el controlador de red de Cisco Terminal Service (TS) Agent podría permitir a un atacante remoto y autenticado eludir las reglas del cortafuegos que están asociadas con la cuenta del atacante. Esta vulnerabilidad se debe a una asignación incorrecta de las conexiones de red a las cuentas de usuario. Un atacante con credenciales de al menos nivel de usuario podría explotar esta vulnerabilidad enviando tráfico de red manipulado a un dispositivo afectado. Un exploit exitoso podría permitir al atacante heredar las reglas del cortafuegos asociadas con un usuario diferente en el sistema.

Information

Published : 2026-08-05 17:16

Updated : 2026-10-23 21:10

NVD link : CVE-2026-20028

Mitre link : CVE-2026-20028

CVE.ORG link : CVE-2026-20028

JSON object : View

Products Affected

No product.

CWE

CWE-266

Incorrect Privilege Assignment

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