Privilege escalation in Cisco Terminal Services Agent
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.0 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (28.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 28th percentile — 28.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
- Cisco Terminal Services Agent — versions TSAgent-1.3, TSAgent-1.4.2, TSAgent-1.2
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-20028?
- CVE-2026-20028 is a medium-severity vulnerability in Cisco Terminal Services Agent, classified under Incorrect Privilege Assignment. CVSS score: 5.0/10. Published 2026-08-05.
- How severe is CVE-2026-20028?
- Medium severity. CVSS v3 base score is 5.0 out of 10.