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CVE-2026-105981NVD status: Deferred

TK100: Improper Neutralization of Special Elements used in an OS Command

CVE-2026-105981 is a high-severity improper neutralization of special elements used in an OS command vulnerability in TK100 from Welotec, with a CVSS 3.1 base score of 7.2 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, without any action from a user. The record lists version 3.5.116 as the first without the flaw, so updating TK100 to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.36% 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 TK100 to 3.5.116 or a later version.
  2. Update TK500-v2 to 1.0.124 or a later version.
  3. Update TK500-v3 to 1.0.123 or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
WelotecTK100before 3.5.1163.5.116
WelotecTK500-v2before 1.0.1241.0.124
WelotecTK500-v3before 1.0.1231.0.123

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
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
HighAdministrator-level access is required first.
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:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (cert.vde.com).

Scoring systemScoreSeverityScored by
CVSS 4.08.6HighCNA (cert.vde.com)
CVSS 3.17.2HighCNA (cert.vde.com)

Official description

Improper input validation in the Digital I/O function may allow a remote attacker with high privileges to inject operating system commands and execute them with root privileges.

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

The underlying weakness: Improper Neutralization of Special Elements used in an OS Command

The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command before it is sent to a downstream component.

How developers prevent this class of flaw

  • If at all possible, use library calls rather than external processes to recreate the desired functionality.
  • For any data that will be used to generate a command to be executed, keep as much of that data out of external control as possible. For example, in web applications, this may require storing the data locally in the session's state instead of sending it out to the client in a hidden form field.
  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

More Improper Neutralization of Special Elements used in an OS Command vulnerabilities (CWE-78)

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 TK100

All TK100 vulnerabilities

Recent Improper Neutralization of Special Elements used in an OS Command vulnerabilities

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