Dsknet: Unrestricted Upload of File with Dangerous Type
CVE-2022-24688 is a high-severity unrestricted upload of file with dangerous type vulnerability in Dsknet from Dsk, 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 Dsknet versions: 2.16.136.0; 2.17.136.5. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 3.98% chance of exploitation within 30 days, which is in the top 9.35% of all scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of Dsknet you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on dsk.lu for workarounds and exact fixed builds.
Affected products and versions
Version data comes from NVD's product matching. 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.
Official description
An issue was discovered in DSK DSKNet 2.16.136.0 and 2.17.136.5. The Touch settings allow unrestricted file upload (and consequently Remote Code Execution) via PDF upload with PHP content and a .php extension. The attacker must hijack or obtain privileged user access to the Parameters page in order to exploit this issue. (That can be easily achieved by exploiting the Broken Access Control with further Brute-force attack or SQL Injection.) The uploaded file is stored within the database and copied to the sync web folder if the attacker visits a certain .php?action= page.
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
- CVE record published.
- Record last changed materially (score, affected products, status or references).
References
Advisories
Technical write-ups (may include proof of concept)
- github.com/post-cyberlabs/CVE-Advisory/blob/main/CVE-2022-24688-92.pdfExploit, Third Party Advisory
Other vulnerabilities in Dsknet
- 7.1 High severity
- 8.2 High severity
Recent Unrestricted Upload of File with Dangerous Type vulnerabilities
- 7.2 High severity
- 9.8 Critical severity
- 8.8 High severity
- 8.0 High severity
- 8.0 High severity
- 8.0 High severity
Spotted an error? Tell us.