CyberSecBulletin
CVE-2026-92374NVD status: Awaiting Analysis

Full Client: Time-of-check Time-of-use (TOCTOU) Race Condition

Published Updated By the CyberSecBulletin desk

CVE-2026-92374 is a high-severity time-of-check time-of-use (TOCTOU) race condition vulnerability in Full Client from TeamViewer, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 15.83, 14.7.48868, 13.2.154007 as the first without the flaw, so updating Full Client to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.09% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Full Client to 15.83 or 14.7.48868 or 13.2.154007, whichever matches your release line, or a later version.
  2. Update Host to 15.83 or 14.7.48868 or 13.2.154007, whichever matches your release line, or a later version.
  3. Read the advisory on teamviewer.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
TeamViewerFull Clientbefore 15.83; 14.7.0 up to, but not including, 14.7.48868; 13.2.0 up to, but not including, 13.2.15400715.83, 14.7.48868, 13.2.154007
TeamViewerHostbefore 15.83; 14.7.0 up to, but not including, 14.7.48868; 13.2.0 up to, but not including, 13.2.15400715.83, 14.7.48868, 13.2.154007

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (teamviewer.com).

Official description

A time-of-check time-of-use (TOCTOU) race condition combined with improper symbolic link handling in the privileged helper of TeamViewer Full Client and Host prior to version 15.83 for macOS allows a local attacker with low privileges to bypass installer package verification and install a malicious package. Successful exploitation can lead to local privilege escalation to root.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Time-of-check Time-of-use (TOCTOU) Race Condition

The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check.

How developers prevent this class of flaw

  • The most basic advice for TOCTOU vulnerabilities is to not perform a check before the use. This does not resolve the underlying issue of the execution of a function on a resource whose state and identity cannot be assured, but it does help to limit the false sense of security given by the check.
  • When the file being altered is owned by the current user and group, set the effective gid and uid to that of the current user and group when executing this statement.
  • Limit the interleaving of operations on files from multiple processes.

More Time-of-check Time-of-use (TOCTOU) Race Condition vulnerabilities (CWE-367)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Full Client

All Full Client vulnerabilities

Recent Time-of-check Time-of-use (TOCTOU) Race Condition vulnerabilities

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