CyberSecBulletin
CVE-2024-3904NVD status: Deferred

MELIPC Series MI5122-VW: Incorrect Default Permissions

CVE-2024-3904 is a high-severity incorrect default permissions vulnerability in MELIPC Series MI5122-VW from Mitsubishi Electric, with a CVSS 3.1 base score of 8.8 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. Affected MELIPC Series MI5122-VW versions: Firmware versions "05" to "07". The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.17% 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 MELIPC Series MI5122-VW you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on mitsubishielectric.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
Mitsubishi ElectricMELIPC Series MI5122-VWFirmware versions "05" to "07"Not stated
Mitsubishimelipc_mi5122-vw_firmware05 through 07Not 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.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
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:C/C:H/I:H/A:H. Scored by CNA (yd.MitsubishiElectric.co.jp).

Official description

Incorrect Default Permissions vulnerability in Smart Device Communication Gateway preinstalled on MELIPC Series MI5122-VW firmware versions "05" to "07" allows a local attacker to execute arbitrary code by saving a malicious file to a specific folder. As a result, the attacker may disclose, tamper with, destroy or delete information in the product, or cause a denial-of-service (DoS) condition on the product.

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

The underlying weakness: Incorrect Default Permissions

During installation, installed file permissions are set to allow anyone to modify those files.

How developers prevent this class of flaw

  • The architecture needs to access and modification attributes for files to only those users who actually require those actions.
  • Compartmentalize the system to have safe areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.

More Incorrect Default Permissions vulnerabilities (CWE-276)

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 MELIPC Series MI5122-VW

All MELIPC Series MI5122-VW vulnerabilities

Recent Incorrect Default Permissions vulnerabilities

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