CyberSecBulletin
CVE-2025-11500NVD status: Deferred

Lan Kontroler v3.5: Insertion of Sensitive Information Into Sent Data

CVE-2025-11500 is a high-severity insertion of sensitive information into sent data vulnerability in Lan Kontroler v3.5 from Tinycontrol, with a CVSS 4.0 base score of 8.7 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. The record lists version 1.67 as the first without the flaw, so updating Lan Kontroler v3.5 to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.37% 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 Lan Kontroler v3.5 to 1.67 or a later version.
  2. Update LK3.9 to 1.75 or a later version.
  3. Update LK4 to 1.38 or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
TinycontrolLan Kontroler v3.5before 1.671.67
TinycontrolLK3.9before 1.751.75
TinycontrolLK4before 1.381.38
TinycontroltcPDUbefore 1.361.36

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
AdjacentThe attacker must be on the same local network segment.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Attack requirements
NoneThe attack does not depend on a particular deployment or configuration.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Confidentiality (vulnerable system)
HighSerious loss of confidentiality on the vulnerable system.
Integrity (vulnerable system)
HighSerious loss of integrity on the vulnerable system.
Availability (vulnerable system)
HighSerious loss of availability on the vulnerable system.
Confidentiality (other systems)
NoneNo loss of confidentiality on systems beyond the vulnerable one.
Integrity (other systems)
NoneNo loss of integrity on systems beyond the vulnerable one.
Availability (other systems)
NoneNo loss of availability on systems beyond the vulnerable one.

Vector: CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. Scored by CNA (cert.pl).

Official description

Tinycontrol devices such as tcPDU and LAN Controllers LK3.5, LK3.9 and LK4 have two separate authentication mechanisms - one solely for interface management and one for protecting all other server resources. When the latter is turned off (which is a default setting), an unauthenticated attacker on the local network can obtain usernames and encoded passwords for interface management portal by inspecting the HTTP response of the server when visiting the login page, which contains a JSON file with these details. Both normal and admin users credentials are exposed. This issue has been fixed in firmware versions: 1.36 (for tcPDU), 1.67 (for LK3.5 - hardware versions: 3.5, 3.6, 3.7 and 3.8), 1.75 (for LK3.9 - hardware version 3.9) and 1.38 (for LK4 - hardware version 4.0).

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

The underlying weakness: Insertion of Sensitive Information Into Sent Data

The code transmits data to another actor, but a portion of the data includes sensitive information that should not be accessible to that actor.

How developers prevent this class of flaw

  • Specify which data in the software should be regarded as sensitive. Consider which types of users should have access to which types of data.
  • Ensure that any possibly sensitive data specified in the requirements is verified with designers to ensure that it is either a calculated risk or mitigated elsewhere. Any information that is not necessary to the functionality should be removed in order to lower both the overhead and the possibility of security sensitive data being sent.
  • Setup default error messages so that unexpected errors do not disclose sensitive information.

More Insertion of Sensitive Information Into Sent Data vulnerabilities (CWE-201)

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 Lan Kontroler v3.5

All Lan Kontroler v3.5 vulnerabilities

Recent Insertion of Sensitive Information Into Sent Data vulnerabilities

Spotted an error? Tell us.