CyberSecBulletin
CVE-2023-0862NVD status: Modified

NSRW: Improper Limitation of a Pathname to a Restricted Directory

Published Updated By the CyberSecBulletin desk

CVE-2023-0862 is a high-severity improper limitation of a pathname to a restricted directory vulnerability in NSRW from NetModule, 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 versions 4.3.0.119, 4.4.0.118, 4.6.0.105 as the first without the flaw, so updating NSRW to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 2.35% chance of exploitation within 30 days, higher than 84% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update NSRW to 4.3.0.119 or 4.4.0.118 or 4.6.0.105 or 4.7.0.103, whichever matches your release line, or a later version.
  2. Update Netmodule Router Software to 4.3.0.119 or 4.4.0.118 or 4.6.0.105 or 4.7.0.103, whichever matches your release line, or a later version.
  3. Read the advisory on onekey.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
NetModuleNSRW4.3.0.0 up to, but not including, 4.3.0.119; 4.4.0.0 up to, but not including, 4.4.0.118; 4.6.0.0 up to, but not including, 4.6.0.105; 4.7.0.0 up to, but not including, 4.7.0.1034.3.0.119, 4.4.0.118, 4.6.0.105, 4.7.0.103
NetmoduleNetmodule Router Software4.3.0.0 up to, but not including, 4.3.0.119; 4.4.0.0 up to, but not including, 4.4.0.118; 4.6.0.0 up to, but not including, 4.6.0.105; 4.7.0.0 up to, but not including, 4.7.0.1034.3.0.119, 4.4.0.118, 4.6.0.105, 4.7.0.103

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
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.

Scoring systemScoreSeverityScored by
CVSS 3.17.2HighCNA (onekey.com)
CVSS 3.18.8HighNVD

Official description

The NetModule NSRW web administration interface is vulnerable to path traversals, which could lead to arbitrary file uploads and deletion. By uploading malicious files to the web root directory, authenticated users could gain remote command execution with elevated privileges. This issue affects NSRW: from 4.3.0.0 before 4.3.0.119, from 4.4.0.0 before 4.4.0.118, from 4.6.0.0 before 4.6.0.105, from 4.7.0.0 before 4.7.0.103.

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

The underlying weakness: Improper Limitation of a Pathname to a Restricted Directory

The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.

How developers prevent this class of flaw

  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
  • Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth.

More Improper Limitation of a Pathname to a Restricted Directory vulnerabilities (CWE-22)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in NSRW

All NSRW vulnerabilities

Recent Improper Limitation of a Pathname to a Restricted Directory vulnerabilities

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