DIR-825: Improper Neutralization of Special Elements used in an OS Command
CVE-2022-43643 is a high-severity improper neutralization of special elements used in an OS command vulnerability in DIR-825 from D-Link, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. Affected DIR-825 versions: 1.0.9. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.92% chance of exploitation within 30 days, higher than 80% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of DIR-825 you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on supportannouncement.us.dlink.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| D-Link | DIR-825 | 1.0.9 | Not stated |
| D-Link | Dir-825/ee Firmware | 1.0.9 and earlier | Not stated |
| D-Link | Dir-825/ac Firmware | 1.0.9 and earlier | Not 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
- AdjacentThe attacker must be on the same local network segment.
- 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:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 8.8 | High | NVD |
| CVSS 3.0 | 8.8 | High | CNA (trendmicro.com) |
Official description
This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of D-Link DIR-825 1.0.9/EE routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the Generic plugin for the xupnpd service, which listens on TCP port 4044. The issue results from the lack of proper validation of a user-supplied string before using it to execute a system call. An attacker can leverage this vulnerability to execute code in the context of the admin user. Was ZDI-CAN-19460.
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
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Third-party and government advisories
- zerodayinitiative.com/advisories/ZDI-22-1702/Third Party Advisory, VDB Entry
Other vulnerabilities in DIR-825
- 9.8 Critical severity
- 8.0 High severity
- 8.8 High severity
- 7.2 High severity
- 9.8 Critical severity
- 9.8 Critical severity
Recent Improper Neutralization of Special Elements used in an OS Command vulnerabilities
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 8.0 High severity
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