CyberSecBulletin
CVE-2022-42972NVD status: Modified

APC Easy UPS Online Monitoring Software: Incorrect Permission Assignment for Critical Resource

CVE-2022-42972 is a high-severity incorrect permission assignment for critical resource vulnerability in APC Easy UPS Online Monitoring Software from Schneider Electric, with a CVSS 3.1 base score of 7.8 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. The record lists versions V2.5-GA, V2.5-GA-01-22261 as the first without the flaw, so updating APC Easy UPS Online Monitoring Software to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.18% 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 APC Easy UPS Online Monitoring Software to V2.5-GA or V2.5-GA-01-22261, whichever matches your release line, or a later version.
  2. Update Schneider Electric Easy UPS Online Monitoring Software to V2.5-GS or V2.5-GS-01-22261, whichever matches your release line, or a later version.
  3. Update Easy Ups Online Monitoring Software to 2.5-gs-01-22320 or 2.5-gs, whichever matches your release line, or a later version.
  4. Read the advisory on download.schneider-electric.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
Schneider ElectricAPC Easy UPS Online Monitoring SoftwareWindows 7, 10, 11 Windows Server 2016, 2019, 2022 up to, but not including, V2.5-GA; (Windows 11, Windows Server 2019, 2022 up to, but not including, V2.5-GA-01-22261V2.5-GA, V2.5-GA-01-22261
Schneider ElectricSchneider Electric Easy UPS Online Monitoring SoftwareWindows 7, 10, 11 Windows Server 2016, 2019, 2022 up to, but not including, V2.5-GS; Windows 11, Windows Server 2019, 2022 up to, but not including, V2.5-GS-01-22261V2.5-GS, V2.5-GS-01-22261
Schneider ElectricEasy Ups Online Monitoring Softwarebefore 2.5-gs-01-22320; before 2.5-gs2.5-gs-01-22320, 2.5-gs

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
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:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.8HighCNA (se.com)
CVSS 3.17.8HighNVD

Official description

A CWE-732: Incorrect Permission Assignment for Critical Resource vulnerability exists that could cause local privilege escalation when a local attacker modifies the webroot directory. Affected Products: APC Easy UPS Online Monitoring Software (Windows 7, 10, 11 & Windows Server 2016, 2019, 2022 - Versions prior to V2.5-GA), APC Easy UPS Online Monitoring Software (Windows 11, Windows Server 2019, 2022 - Versions prior to V2.5-GA-01-22261), Schneider Electric Easy UPS Online Monitoring Software (Windows 7, 10, 11 & Windows Server 2016, 2019, 2022 - Versions prior to V2.5-GS), Schneider Electric Easy UPS Online Monitoring Software (Windows 11, Windows Server 2019, 2022 - Versions prior to V2.5-GS-01-22261)

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

The underlying weakness: Incorrect Permission Assignment for Critical Resource

The product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.

How developers prevent this class of flaw

  • When using a critical resource such as a configuration file, check to see if the resource has insecure permissions (such as being modifiable by any regular user), and generate an error or even exit the software if there is a possibility that the resource could have been modified by an unauthorized party.
  • Divide the software into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully defining distinct user groups, privileges, and/or roles. Map these against data, functionality, and the related resources. Then set the permissions accordingly. This will allow you to maintain more fine-grained control over your resources.
  • During program startup, explicitly set the default permissions or umask to the most restrictive setting possible. Also set the appropriate permissions during program installation. This will prevent you from inheriting insecure permissions from any user who installs or runs the program.

More Incorrect Permission Assignment for Critical Resource vulnerabilities (CWE-732)

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 APC Easy UPS Online Monitoring Software

All APC Easy UPS Online Monitoring Software vulnerabilities

Recent Incorrect Permission Assignment for Critical Resource vulnerabilities

Spotted an error? Tell us.