CVE-2026-20028 Details
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.
A vulnerability exists in the network driver of Cisco Terminal Services (TS) Agent, allowing an authenticated, remote attacker to bypass firewall rules linked to the attacker's account. This issue arises from an incorrect mapping of network connections to user accounts. An attacker with user-level credentials could exploit this by sending crafted network traffic to an affected device, potentially inheriting firewall rules from a different user.
Users are advised to upgrade to Cisco TS Agent version 1.4.3 or later. For guidance on obtaining the update, consult the Cisco Support and Downloads page or contact the Cisco Technical Assistance Center (TAC).
Metrics
CVSS 4.0 Severity and Vector Strings:
No CVSS 4.0 data is available for this CVE.
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
CISA-ADP
Assessed Aug 5, 2026References to Advisories, Solutions, and Tools
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| URL | Source(s) | Tag(s) |
|---|---|---|
| https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ts-agent-fw-bypass-MYBTMrev | [email protected] |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-266 | Incorrect Privilege Assignment | [email protected] |
Affected Products
No affected product data is available for this CVE.
Change History
2 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Aug 5, 2026 | CVE Modified | CISA-ADP |
| Aug 5, 2026 | New CVE Received | [email protected] |