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CVE-2026-12504NVD status: Deferred

LIP-ME20xC: Improper Authentication

CVE-2026-12504 is a high-severity improper authentication vulnerability in LIP-ME20xC from Loytec, with a CVSS 4.0 base score of 8.4 out of 10. It can be exploited with local access to the system by an attacker with administrator privileges, without any action from a user. Affected LIP-ME20xC versions: 8.4.16 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.19% 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. Check which version of LIP-ME20xC you run against the affected versions below, and install the vendor's latest release.

Affected products and versions

VendorProductAffected versionsFixed in
LoytecLIP-ME20xC8.4.16 and earlierNot stated
LoytecL-INX8.4.16 and earlierNot stated
LoytecL-GATE8.4.16 and earlierNot stated
LoytecL-ROC8.4.16 and earlierNot stated
LoytecL-IOB8.4.16 and earlierNot stated
LoytecL-DALI8.4.16 and earlierNot stated
LoytecL-VIS8.4.16 and earlierNot stated
LoytecL-PAD8.4.16 and earlierNot stated

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.
Attack requirements
NoneThe attack does not depend on a particular deployment or configuration.
Privileges required
HighAdministrator-level access is required first.
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:L/AC:L/AT:N/PR:H/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 (ncsc.ch).

Official description

Improper Authentication (CWE-287) in the PAM configuration in Loytec LIP-ME201C, L-INX, L-GATE, L-ROC, L-IOB, L-DALI, L-VIS and L-PAD through 8.4.16 on LINX-A64 allows a local attacker to authenticate as a uid=0 account without a password and obtain a root shell via an `/etc/passwd` entry with an empty password field.

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

The underlying weakness: Improper Authentication

When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.

How developers prevent this class of flaw

  • Use an authentication framework or library such as the OWASP ESAPI Authentication feature.

More Improper Authentication vulnerabilities (CWE-287)

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 LIP-ME20xC

All LIP-ME20xC vulnerabilities

Recent Improper Authentication vulnerabilities

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