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Severe, 6 weeks1496Projects326

1496 severe, 6 weeks · 326 projects

CiscoCVE-2026-20211

Cisco Identity Services Engine Software: remote code execution

Cisco

CVE-2026-20211 · Published Sep 16, 2026 · updated Sep 17, 2026

Critical9.1
No fix yet
Cisco advisory

A vulnerability in Cisco ISE 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 high-privileged administrative credentials.

This vulnerability is due to insecure deserialization of Java objects by the affected software. An attacker could exploit this vulnerability by sending a crafted serialized Java object 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 DoS condition. In that condition, endpoints that have not already authenticated would be unable to access the network until the node is restored.

Affected versions

PackageAffectedFixed in
Cisco Identity Services Engine Software
Product
<= 3.1.0No fix yet
<= 3.1.0 p1No fix yet
<= 3.1.0 p3No fix yet
<= 3.1.0 p2No fix yet
Details and references

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