What’s Vulnerable › Vulnerabilities
CVE-2026-20028: Cisco Terminal Services Agent Firewall Rules Bypass Vulnerability
- Severity: medium (CVSS 5.0 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.3% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-08-05 · updated 2026-10-23
- Weakness: CWE-266
Description
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.
Affected products
- Cisco Terminal Services Agent: TSAgent-1.3, TSAgent-1.4.2, TSAgent-1.2, TSAgent-1.4, TSAgent-1.0, TSAgent-1.4.1 (+1)
References
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