Cyber Resilience

CVE-2026-20181

Critical

Published: 17 June 2026

Published
17 June 2026
Modified
22 June 2026
KEV Added
—
Patch
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CVSS Score v3.1 9.1 CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.0075 50.3th percentile
Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2026-20181 is a critical-severity Path Traversal (CWE-22) vulnerability in Cisco Identity Services Engine. Its CVSS base score is 9.1 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 49.7% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

A01:2025 Broken Access Control

EU & UK References

Vulnerability details

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…

more

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.

CWE(s)
CWE-22

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
Why these techniques?

CVE enables remote command execution on Cisco ISE via crafted HTTP requests to a public-facing service (T1190) and subsequent privilege escalation from user to root (T1068).

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

Affected Assets

cisco
identity services engine
3.3.0, 3.4.0, 3.5.0 · ≤ 3.3.0
cisco
identity services engine passive identity connector
3.3.0, 3.4.0, 3.5.0 · ≤ 3.3.0

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

SI-10 Information Input Validation
addresses: CWE-22

Validates pathnames and filenames to prevent traversal outside intended directories.

References