Path Traversal in Cisco Identity Services Engine Software

CVE-2026-20181

A vulnerability in Cisco ISE and ISE-PIC could allow an authenticated, remote attacker to execute arbitrary commands on the underlying operating system of an affected device. To exploit this vulnerability, the attacker must have valid administrative credentials. This vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by sending a crafted HTTP request to an affected device. A successful exploit could allow the attacker to obtain user-level access to the underlying operating system and then elevate privileges to root. In single-node deployments, successful exploitation of this vulnerability could cause the affected ISE node to become unavailable, resulting in a denial of service (DoS) condition. In that condition, endpoints that have not already authenticated would be unable to access the network until the node is restored.

Vulnerability class: Path Traversal (Directory Traversal)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.089 (95.1th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 95th percentile — 95.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-20181: held from 0.089 to 0.089.

EPSS over last 30 days · oldest: 0.089 · newest: 0.089 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-20181?
CVE-2026-20181 is a critical-severity vulnerability in Cisco Identity Services Engine Software, classified under Path Traversal. CVSS score: 9.1/10. Published 2026-06-17.
How severe is CVE-2026-20181?
Critical severity. CVSS v3 base score is 9.1 out of 10.