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CiscoCVE-2026-20028

Cisco Terminal Services Agent: authenticated, remote attacker could bypass...

Medium5.0CVE-2026-20028 · Published Aug 5, 2026 · updated Aug 6, 2026

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.

Cisco advisory

Affected versions

PackageAffectedFixed in
Cisco Terminal Services Agent
Product
<= TSAgent-1.3No fix yet
<= TSAgent-1.4.2No fix yet
<= TSAgent-1.2No fix yet
<= TSAgent-1.4No fix yet
Details and references

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