VulnerabilityPublished 22 Aug 2025

CVE-2025-55581: D-Link DCS-825L firmware · Download of Code Without Integrity Check

Source CVE Database V5

Not known to be exploited · CVSS 7.3 High.

Data as of 26 Oct 2026, 14:05 UTC

CVSS 3.1 base score

7.3High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.1% chance of exploitation in 30 days – higher than 8% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:L

Attack Vector: Local
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: High
Availability: Low

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Local: The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either: the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or remotely (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., tricking a legitimate user into opening a malicious document).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the impacted component are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 22 Aug 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

AI-suggested

To mitigate this vulnerability, organizations should first verify the firmware version of their D-Link DCS-825L devices and upgrade to a patched version once available from D-Link. Until a patch is released, physical security controls should be enhanced to prevent unauthorized physical access to devices, especially access to UART interfaces or other hardware debugging ports. Network segmentation should be employed to isolate IoT devices like cameras from critical network segments, limiting the potential impact of a compromised device. Monitoring for unusual device behavior or unexpected network traffic from cameras can help detect exploitation attempts. Additionally, organizations should consider implementing runtime integrity monitoring solutions that can detect unauthorized binary modifications on embedded devices. For long-term mitigation, vendors should be encouraged to implement cryptographic integrity checks and secure boot mechanisms in firmware to prevent unauthorized binary replacement. Finally, incident response plans should include procedures for handling IoT device compromises, including forensic analysis and secure device replacement.

Description

D-Link DCS-825L firmware version 1.08.01 and possibly prior versions contain an insecure implementation in the mydlink-watch-dog.sh script. The script monitors and respawns the `dcp` and `signalc` binaries without validating their integrity, origin, or permissions. An attacker with filesystem access (e.g., via UART or firmware modification) may replace these binaries to achieve persistent arbitrary code execution with root privileges. The issue stems from improper handling of executable trust and absence of integrity checks in the watchdog logic.

Impact

For European organizations, this vulnerability poses a substantial risk, especially for those deploying D-Link DCS-825L cameras in their security infrastructure. Compromise of these devices could lead to unauthorized surveillance, data leakage, or use of the compromised cameras as footholds for lateral movement within corporate networks. Given that the vulnerability allows root-level persistent code execution, attackers could install backdoors, manipulate video feeds, or use the device as a pivot point to attack other network assets. This is particularly critical for sectors with stringent privacy and security requirements, such as government agencies, financial institutions, and critical infrastructure operators in Europe. Additionally, compromised cameras could violate GDPR regulations if personal data is exposed or manipulated, leading to legal and financial repercussions. The persistence aspect means that even device resets or watchdog restarts will not remove the attacker’s control, complicating incident response and remediation efforts.

CWE-494Download of Code Without Integrity Check (opens in a new tab)
Base weaknessLikelihood of exploit: MediumOWASP Top 10 A08:2025: Software or Data Integrity Failures (opens in a new tab)
The product downloads source code or an executable from a remote location and executes the code without sufficiently verifying the origin and integrity of the code.
Implementation
Perform proper forward and reverse DNS lookups to detect DNS spoofing.
Architecture and Design · Operation
Encrypt the code with a reliable encryption scheme before transmitting.
Architecture and Design · Libraries or Frameworks
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
OWASP Cheat Sheets
Docker Security (opens in a new tab)
XML Security (opens in a new tab)
Software Supply Chain Security (opens in a new tab)
Infrastructure as Code (opens in a new tab)
OWASP ASVS 4.0.3
V1.14.2 (opens in a new tab)
V10.3.1 (opens in a new tab)
V13.3.2 (opens in a new tab)
Attack patterns
Malicious Software Download (opens in a new tab)
Malicious Software Update (opens in a new tab)
Malicious Automated Software Update via Redirection (opens in a new tab)
Malicious Manual Software Update (opens in a new tab)
Open-Source Library Manipulation (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-306Missing Authentication for Critical Function (opens in a new tab)
Base weaknessLikelihood of exploit: HighCWE Top 25 (2025): #21OWASP Top 10 A07:2025: Authentication Failures (opens in a new tab)
The product does not perform any authentication for functionality that requires a provable user identity or consumes a significant amount of resources.
Architecture and Design
Divide the software into anonymous, normal, privileged, and administrative areas. Identify which of these areas require a proven user identity, and use a centralized authentication capability.
Architecture and Design
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…
Architecture and Design
Where possible, avoid implementing custom, "grow-your-own" authentication routines and consider using authentication capabilities as provided by the surrounding framework, operating system, or environment.
OWASP Cheat Sheets
OWASP Authentication (opens in a new tab)
OWASP ASVS 4.0.3
V1.2.3 (opens in a new tab)
V1.2.2 (opens in a new tab)
V1.2.4 (opens in a new tab)
Attack patterns
Choosing Message Identifier (opens in a new tab)
Force the System to Reset Values (opens in a new tab)
Using Unpublished Interfaces or Functionality (opens in a new tab)
Cross Site Request Forgery (opens in a new tab)
Communication Channel Manipulation (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).
CWE-269Improper Privilege Management (opens in a new tab)
Class weaknessLikelihood of exploit: MediumOWASP Top 10 A06:2025: Insecure Design (opens in a new tab)
The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor.
MITRE discourages mapping vulnerabilities to this broad entry; the root cause is usually a more specific weakness.
Architecture and Design · Operation
Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.
Architecture and Design · Separation of Privilege
Follow the principle of least privilege when assigning access rights to entities in a software system.
Architecture and Design · Separation of Privilege
Consider following the principle of separation of privilege. Require multiple conditions to be met before permitting access to a system resource.
OWASP Cheat Sheets
Docker Security (opens in a new tab)
Third Party Javascript Management (opens in a new tab)
Virtual Patching (opens in a new tab)
Secure Design Principles (opens in a new tab)
OWASP ASVS 4.0.3
V1.4.4 (opens in a new tab)
V1.4.5 (opens in a new tab)
V1.10.1 (opens in a new tab)
Attack patterns
Restful Privilege Elevation (opens in a new tab)
Privilege Abuse (opens in a new tab)
Privilege Escalation (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 22 Aug 2025, 18:17 UTC

WeaknessesCWE-494, CWE-306, CWE-269

Technical details

References

Community reviews

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