Cyber Posture

CVE-2025-20206

High

Published: 05 March 2025

Published
05 March 2025
Modified
22 July 2025
KEV Added
Patch
CVSS Score 7.1 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
EPSS Score 0.0003 7.3th percentile
Risk Priority 14 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-20206 is a high-severity Improper Verification of Cryptographic Signature (CWE-347) vulnerability in Cisco Secure Client. Its CVSS base score is 7.1 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 7.3th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 CM-14 (Signed Components) and SI-7 (Software, Firmware, and Information Integrity).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploitation for Privilege Escalation (T1068) and 1 other technique. What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

preventdetect

Requires integrity-checking mechanisms for software loaded at runtime, directly preventing DLL hijacking by detecting unauthorized or tampered DLLs in Cisco Secure Client.

prevent

Mandates digital signatures for system components like DLLs, ensuring only verified components are loaded despite IPC-triggered hijacking attempts.

prevent

Validates inputs such as crafted IPC messages to the Cisco Secure Client process, blocking exploitation that leads to insufficient resource validation and DLL loading.

MITRE ATT&CK Enterprise TechniquesAI

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
T1574.001 DLL Stealth
Adversaries may abuse dynamic-link library files (DLLs) in order to achieve persistence, escalate privileges, and evade defenses.
Why these techniques?

Vulnerability enables DLL hijacking via crafted IPC messages leading to arbitrary code execution with SYSTEM privileges, directly mapping to exploitation for privilege escalation (T1068) and DLL side-loading (T1574.002).

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

NVD Description

A vulnerability in the interprocess communication (IPC) channel of Cisco Secure Client for Windows could allow an authenticated, local attacker to perform a DLL hijacking attack on an affected device if the Secure Firewall Posture Engine, formerly HostScan, is installed…

more

on Cisco Secure Client. This vulnerability is due to insufficient validation of resources that are loaded by the application at run time. An attacker could exploit this vulnerability by sending a crafted IPC message to a specific Cisco Secure Client process. A successful exploit could allow the attacker to execute arbitrary code on the affected machine with SYSTEM privileges. To exploit this vulnerability, the attacker must have valid user credentials on the Windows system.

Deeper analysisAI

CVE-2025-20206 is a vulnerability in the interprocess communication (IPC) channel of Cisco Secure Client for Windows that enables a DLL hijacking attack. It affects devices where the Secure Firewall Posture Engine, formerly known as HostScan, is installed on Cisco Secure Client. The flaw arises from insufficient validation of resources loaded by the application at runtime.

An authenticated local attacker with valid user credentials on the Windows system can exploit this vulnerability by sending a crafted IPC message to a specific Cisco Secure Client process. Successful exploitation allows the attacker to execute arbitrary code on the affected machine with SYSTEM privileges. The vulnerability has a CVSS v3.1 base score of 7.1 (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N) and is associated with CWE-347.

The Cisco Security Advisory provides details on this issue, including mitigation recommendations, at https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-secure-dll-injection-AOyzEqSg.

Details

CWE(s)

Affected Products

cisco
secure client
≤ 5.1.8.105

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References