CyberSecBulletin
CVE-2023-33480NVD status: Modified

remote_clinic: Unrestricted Upload of File with Dangerous Type

CVE-2023-33480 is a high-severity unrestricted upload of file with dangerous type vulnerability in remote_clinic from RemoteClinic, 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 remote_clinic versions: 2.0. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 2.44% chance of exploitation within 30 days, higher than 85% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of remote_clinic you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
Remoteclinicremote_clinic2.0Not 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 3.18.8HighNVD
CVSS 3.18.8HighCISA (ADP)

Official description

RemoteClinic 2.0 contains a critical vulnerability chain that can be exploited by a remote attacker with low-privileged user credentials to create admin users, escalate privileges, and execute arbitrary code on the target system via a PHP shell. The vulnerabilities are caused by a lack of input validation and access control in the staff/register.php endpoint and the edit-my-profile.php page. By sending a series of specially crafted requests to the RemoteClinic application, an attacker can create admin users with more privileges than their own, upload a PHP file containing arbitrary code, and execute arbitrary commands via the PHP shell.

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

The underlying weakness: Unrestricted Upload of File with Dangerous Type

The product allows the upload or transfer of dangerous file types that are automatically processed within its environment.

How developers prevent this class of flaw

  • Generate a new, unique filename for an uploaded file instead of using the user-supplied filename, so that no external input is used at all.
  • When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.
  • Consider storing the uploaded files outside of the web document root entirely. Then, use other mechanisms to deliver the files dynamically.

More Unrestricted Upload of File with Dangerous Type vulnerabilities (CWE-434)

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

Advisories

Other vulnerabilities in remote_clinic

All remote_clinic vulnerabilities

Recent Unrestricted Upload of File with Dangerous Type vulnerabilities

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