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CVE-2023-22653NVD status: Modified

UR32L: Improper Neutralization of Special Elements used in an OS Command

CVE-2023-22653 is a high-severity improper neutralization of special elements used in an OS command vulnerability in UR32L from MileSight, 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. Affected UR32L versions: v32.3.0.5. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 5.78% chance of exploitation within 30 days, which is in the top 6.79% of all scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of UR32L you run against the affected versions below, and install the vendor's latest release.

Affected products and versions

VendorProductAffected versionsFixed in
MilesightUR32Lv32.3.0.5Not stated
Milesightur32l_firmware32.3.0.5Not 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
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 3.18.8HighCNA (cisco.com)
CVSS 3.18.8HighNVD

Official description

An OS command injection vulnerability exists in the vtysh_ubus tcpdump_start_cb functionality of Milesight UR32L v32.3.0.5. A specially crafted HTTP request can lead to command execution. An authenticated attacker can send an HTTP request to trigger this vulnerability.

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

The underlying weakness: Improper Neutralization of Special Elements used in an OS Command

The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command before it is sent to a downstream component.

How developers prevent this class of flaw

  • If at all possible, use library calls rather than external processes to recreate the desired functionality.
  • For any data that will be used to generate a command to be executed, keep as much of that data out of external control as possible. For example, in web applications, this may require storing the data locally in the session's state instead of sending it out to the client in a hidden form field.
  • 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.

More Improper Neutralization of Special Elements used in an OS Command vulnerabilities (CWE-78)

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

Technical write-ups (may include proof of concept)

Other vulnerabilities in UR32L

All UR32L vulnerabilities

Recent Improper Neutralization of Special Elements used in an OS Command vulnerabilities

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