CyberSecBulletin
CVE-2025-21624NVD status: Analyzed

clipbucket-v5: Unrestricted Upload of File with Dangerous Type

CVE-2025-21624 is a critical-severity unrestricted upload of file with dangerous type vulnerability in clipbucket-v5 from MacWarrior, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected clipbucket-v5 versions: < 5.5.1 - 239. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.23% chance of exploitation within 30 days, higher than 70% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update Clipbucket to 5.5.1-239 or a later version.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
MacWarriorclipbucket-v5< 5.5.1 - 239Not stated
OxygenzClipbucket5.3 up to, but not including, 5.5.1-2395.5.1-239

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
NoneNo account or login is needed.
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:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (github.com).

Official description

ClipBucket V5 provides open source video hosting with PHP. Prior to 5.5.1 - 239, a file upload vulnerability exists in the Manage Playlist functionality of the application, specifically surrounding the uploading of playlist cover images. Without proper checks, an attacker can upload a PHP script file instead of an image file, thus allowing a webshell or other malicious files to be stored and executed on the server. This attack vector exists in both the admin area and low-level user area. This vulnerability is fixed in 5.5.1 - 239.

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: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in clipbucket-v5

All clipbucket-v5 vulnerabilities

Recent Unrestricted Upload of File with Dangerous Type vulnerabilities

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