VulnerabilityPublished 5 Mar 2025Updated 26 Feb 2026

CVE-2025-20206: Cisco Secure Client · Improper Verification of Cryptographic Signature

Affects Cisco Secure ClientSource CVE Database V5

Not known to be exploited · CVSS 7.1 High.

Data as of 26 Oct 2026, 17:16 UTC

CVSS 3.1 base score

7.1High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.1% chance of exploitation in 30 days – higher than 7% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

Attack Vector: Local
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: High
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Local: The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either: the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or remotely (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., tricking a legitimate user into opening a malicious document).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 5 Mar 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
Cisco Cisco Secure Client	Affected 4.9.00086 – 5.1.7.80 42 affected builds	Fixed in–

AI-suggested

Organizations should immediately verify if they are running affected versions of Cisco Secure Client with the Secure Firewall Posture Engine installed. Cisco should be consulted for official patches or updates addressing this vulnerability; applying these updates promptly is the most effective mitigation. If patches are not yet available, consider disabling or uninstalling the Secure Firewall Posture Engine component temporarily to reduce attack surface. Implement strict access controls and monitoring on endpoints to detect unusual IPC activity or DLL loading behavior. Employ application whitelisting and integrity monitoring tools to prevent unauthorized DLL execution. Enforce strong authentication and limit local user privileges to reduce the risk of exploitation by compromised accounts. Regularly audit and review endpoint security configurations and logs for signs of suspicious activity related to IPC channels. Finally, educate users about the risks of credential compromise and enforce multi-factor authentication to minimize the chance of unauthorized local access.

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 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.

Impact

The vulnerability allows an authenticated local attacker to escalate privileges to SYSTEM level, which can lead to full compromise of the affected Windows machine. This includes unauthorized access to sensitive data, manipulation or deletion of critical files, installation of persistent malware, and potential lateral movement within a network. Since Cisco Secure Client is widely used in enterprise environments for secure VPN and endpoint posture enforcement, exploitation could undermine network security and trust. The impact is particularly severe in organizations with high-value assets, regulated data, or critical infrastructure. The requirement for local authentication limits remote exploitation but insider threats or compromised user accounts could leverage this vulnerability to gain elevated privileges. The absence of known exploits in the wild currently reduces immediate risk but does not diminish the urgency for remediation given the potential damage.

References

sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-secure-dll-injection-AOyzEqSg (opens in a new tab)

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Feb 2026, 20:48 UTC

Technical details

References

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