CyberSecBulletin
CVE-2023-47250NVD status: Modified

Mprivacy-tools: Incorrect Default Permissions

Published Updated By the CyberSecBulletin desk

CVE-2023-47250 is a high-severity incorrect default permissions vulnerability in Mprivacy-tools from M-privacy, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists version 4.0.406g as the first without the flaw, so updating Mprivacy-tools to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 1.4% chance of exploitation within 30 days, higher than 73% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Mprivacy-tools to 4.0.406g or a later version.
  2. Update Rsbac-policy-tgpro to 2.0.159 or a later version.
  3. Update Tightgatevnc to 4.1.2-1 or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
M-privacyMprivacy-toolsbefore 4.0.406g4.0.406g
M-privacyRsbac-policy-tgprobefore 2.0.1592.0.159
M-privacyTightgatevncbefore 4.1.2-14.1.2-1

Version data comes from NVD's product matching. 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
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:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Official description

In mprivacy-tools before 2.0.406g in m-privacy TightGate-Pro Server, broken Access Control on X11 server sockets allows authenticated attackers (with access to a VNC session) to access the X11 desktops of other users by specifying their DISPLAY ID. This allows complete control of their desktop, including the ability to inject keystrokes and perform a keylogging attack.

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. Record last changed materially (score, affected products, status or references).

References

Technical write-ups (may include proof of concept)

Recent Incorrect Default Permissions vulnerabilities

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