Full Report
Security researcher Bobby Gould has published a blog post demonstrating a complete exploit chain for CVE-2025-20281, an unauthenticated remote code execution vulnerability in Cisco Identity Services Engine (ISE). [...]
Analysis Summary
# Vulnerability: Critical Cisco ISE Command Injection Leading to Host Root Compromise
## CVE Details
- CVE ID: **Not explicitly provided in the text (referred to as a critical Cisco ISE bug)**
- CVSS Score: **Not explicitly provided in the text (Implied Critical)**
- CWE: **CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')** (Inferred based on attack description)
## Affected Systems
- Products: Cisco ISE (Identity Services Engine)
- Versions: **Not specified in the provided text.**
- Configurations: Vulnerability exploited via a serialized `Java String[]` payload affecting an unspecified component where `Runtime.exec()` is used.
## Vulnerability Description
The vulnerability is an **unauthenticated Remote Code Execution (RCE)** flaw stemming from a command injection vulnerability within Cisco ISE. An attacker can send a specially crafted, serialized Java `String[]` payload. This payload exploits improper handling by Java's `Runtime.exec()` function. The attacker uses `${IFS}` to bypass argument tokenization issues, achieving **arbitrary command execution as the `root` user inside a Docker container.** Furthermore, the exploitation path includes a **successful escape from the privileged Docker container** to gain **root access on the underlying host system** using a known Linux container escape technique involving `cgroups` and `release_agent$.`
## Exploitation
- Status: **Exploited in the wild** (Active exploitation underway)
- Complexity: **Medium** (Requires understanding of Java serialization, command injection bypasses like `${IFS}`, and Docker container escape techniques.)
- Attack Vector: **Network** (Implied, as it's an unauthenticated RCE flaw typically leveraged remotely)
## Impact
- Confidentiality: **High** (Root access allows complete data exfiltration)
- Integrity: **High** (Root access allows modification or destruction of system data)
- Availability: **High** (Root access allows complete denial of service or system compromise)
## Remediation
### Patches
- **Apply the patches** detailed in the corresponding Cisco Security Advisory: [cisco-sa-ise-unauth-rce-ZAd2GnJ6] (Note: The specific patched version numbers were not included in the article snippet).
### Workarounds
- **No workarounds are available** for this vulnerability. Immediate patching is the only recommended action.
## Detection
- Indicators of compromise must be sought within network traffic for specially crafted serialized Java payloads targeting the vulnerable ISE service.
- Detection should focus on unusual process execution originating from vulnerable ISE instances, container breakouts, or unauthorized root privilege escalation on the host operating system.
## References
- Vendor Advisory: (Defanged URL used) hxxps://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-unauth-rce-ZAd2GnJ6
- Researcher Write-up Source (Technical Details): zerodayinitiative.com