CVE-2026-20211
Cisco Identity Services Engine Remote Code Execution Vulnerability
Description
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.
In plain language
AI Act nowIf you run cisco identity services engine software, this is a serious flaw that can let someone with a high-level administrator account take control of the server; treat it as urgent.
Authenticated remote code execution in cisco identity services engine software through insecure Java object deserialization, requiring valid high-privileged administrative credentials and potentially leading to root access.
What to do now
- Check whether you run cisco identity services engine software and identify its installed release and all administrator accounts.
- Restrict high-privileged administrator access to trusted staff and management networks; review and disable unneeded administrator accounts.
- No fixed version is currently available in the findings; ask Cisco or your support provider for the applicable update and deploy it as soon as one is issued.
- Review administrator logins and ISE server activity for unexpected changes or command execution.
CVSS Vector Breakdown
AV:NAttack VectorAC:LAttack ComplexityPR:HPrivileges RequiredUI:NUser InteractionS:CScopeC:HConfidentialityI:HIntegrityA:HAvailabilityWeaknesses
Affected Products
Exploitability
Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.
View exploit detailsAttack Graph
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MITRE ATT&CK
3 techniquesReferences
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