DIR-505: Hidden Functionality
CVE-2026-118579 is a critical-severity hidden functionality vulnerability in DIR-505 from D-Link, 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 DIR-505 versions: 1.10B02. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.79% chance of exploitation within 30 days, higher than 57% of scored CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of DIR-505 you run against the affected versions below, and install the vendor's latest release.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
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 (vuldb.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.9 | High | CNA (vuldb.com) |
| CVSS 3.1 | 9.8 | Critical | CNA (vuldb.com) |
| CVSS 2.0 | 10.0 | High | CNA (vuldb.com) |
Official description
A weakness has been identified in D-Link DIR-505 1.10B02. The impacted element is the function main of the file /secmark1524.cgi of the component Web Management CGI. This manipulation of the argument accu/pass/code/hash/cmds causes backdoor. The attack is possible to be carried out remotely. The exploit has been made available to the public and could be used for attacks.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Hidden Functionality
The product contains functionality that is not documented, not part of the specification, and not accessible through an interface or command sequence that is obvious to the product's users or administrators.
How developers prevent this class of flaw
- Always verify the integrity of the product that is being installed.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other references
Other vulnerabilities in DIR-505
- 10.0 Critical severity
Recent Hidden Functionality vulnerabilities
- 7.0 High severity
- 8.6 High severity
- 8.0 High severity
- 9.8 Critical severity
- 8.7 High severity
- 10.0 Critical severity
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