CVE-2021-1496

SYSTEM code execution via user-writable executable path

Published May 6, 2021 · Updated Nov 8, 2024

Executable hijacking in Cisco AnyConnect Secure Mobility Client for Windows before 4.9.03022 allows local users to execute code as SYSTEM. The installer loads an executable from a user-writable directory, allowing a planted file to run during installation or upgrade. Valid Windows credentials and a local opportunity to place the file before the privileged process accesses it are required.

CVSS severity7.0
High
EPSS probability0.53%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Executable hijacking in Cisco AnyConnect Secure Mobility Client for Windows before 4.9.03022 allows local users to execute code as SYSTEM. The installer loads an executable from a user-writable directory, allowing a planted file to run during installation or upgrade. Valid Windows credentials and a local opportunity to place the file before the privileged process accesses it are required.

The record

CVE
CVE-2021-1496
Published
May 6, 2021
Updated
Nov 8, 2024
Vendor
ClamAV
Product
Cisco Secure Client
Classifications
CWE-427, CWE-378, T1574.005
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. May 6, 2021CVE publishedPublication date reported by the CVE source.
  2. Nov 8, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=n/a

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

ClamAV · Cisco Secure Clientversion=n/a

Published CVSS scores

7.0Cisco Systems, Inc.CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:X/RL:X/RC:X
7.8NISTCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.2NISTAV:L/AC:L/Au:N/C:C/I:C/A:C

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-427Uncontrolled Search Path Element
CWE-378Creation of Temporary File With Insecure Permissions
T1574.005Hijack Execution Flow: Executable Installer File Permissions Weakness

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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