CVE-2021-1536

Cross-user code execution via runtime path handling

Published Jun 4, 2021 · Updated Nov 7, 2024

DLL injection in Cisco Webex App for Windows allows local users to execute code with another user's privileges when the application starts. Runtime directory-path handling accepts a configuration file placed in a specific system path and causes the application to load an attacker-supplied DLL. Exploitation requires valid Windows credentials and user interaction to start the application; the loaded code runs with another user's account privileges.

CVSS severity4.8
Medium
EPSS probability0.33%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

DLL injection in Cisco Webex App for Windows allows local users to execute code with another user's privileges when the application starts. Runtime directory-path handling accepts a configuration file placed in a specific system path and causes the application to load an attacker-supplied DLL. Exploitation requires valid Windows credentials and user interaction to start the application; the loaded code runs with another user's account privileges.

The record

CVE
CVE-2021-1536
Published
Jun 4, 2021
Updated
Nov 7, 2024
Vendor
ClamAV
Product
Webex App
Classifications
CWE-427, T1574.001
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 4, 2021CVE publishedPublication date reported by the CVE source.
  2. Nov 7, 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?

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  1. Affected versionversion=n/a

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

ClamAV · Webex Appversion=n/a

Published CVSS scores

7.8NISTCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.9NISTAV:L/AC:M/Au:N/C:C/I:C/A:C
4.8Cisco Systems, Inc.CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:L/E:X/RL:X/RC:X

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.

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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
T1574.001DLL Search Order Hijacking

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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