CyberSecBulletin
CVE-2024-13723NVD status: Deferred

NagVis: Unrestricted Upload of File with Dangerous Type

CVE-2024-13723 is a high-severity unrestricted upload of file with dangerous type vulnerability in NagVis from Checkmk, with a CVSS 3.1 base score of 7.2 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, without any action from a user. The record lists versions 1.9.42, 2.3.0p10 as the first without the flaw, so updating NagVis to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 1.27% chance of exploitation within 30 days, higher than 70% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update NagVis to 1.9.42 or 2.3.0p10, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
CheckmkNagVisNagVis 1.9.40 up to, but not including, 1.9.42; Checkmk 2.3.0p2 up to, but not including, 2.3.0p101.9.42, 2.3.0p10

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
HighAdministrator-level access is required first.
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:H/UI:N/S:U/C:H/I:H/A:H. Scored by CISA (ADP).

Official description

The "NagVis" component within Checkmk is vulnerable to remote code execution. An authenticated attacker with administrative level privileges is able to upload a malicious PHP file and modify specific settings to execute the contents of the file as PHP.

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: poc, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Patches and release notes

Recent Unrestricted Upload of File with Dangerous Type vulnerabilities

Spotted an error? Tell us.