CVE-2021-34803

Local code execution via unsafe DLL search

Published Jun 16, 2021 · Updated Aug 4, 2024

Uncontrolled DLL loading in TeamViewer before 14.7.48644 on Windows allows local users to execute code in the service process. A Windows system DLL searches the application directory and loads an untrusted DLL there into the TeamViewer service process. Exploitation requires local placement of a crafted DLL and a situation that triggers the affected load path; published details do not identify the exact trigger.

CVSS severity7.8
High
EPSS probability0.47%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Uncontrolled DLL loading in TeamViewer before 14.7.48644 on Windows allows local users to execute code in the service process. A Windows system DLL searches the application directory and loads an untrusted DLL there into the TeamViewer service process. Exploitation requires local placement of a crafted DLL and a situation that triggers the affected load path; published details do not identify the exact trigger.

The record

CVE
CVE-2021-34803
Published
Jun 16, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-427, T1574.001
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 16, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

4.4NIST National Vulnerability DatabaseAV:L/AC:M/Au:N/C:P/I:P/A:P
7.8NIST National Vulnerability DatabaseCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

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
Privilegesunauthenticated
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.

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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