Cyber Resilience

CVE-2025-29040

RCE in Dlink Dir-823X Firmware 240802

Published
17 April 2025
Modified
17 June 2026
Patch / advisory
CVSS Score v3.1 9.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.013 68th percentile
Risk Priority 80 floored blend · peak EPSS

Summary

CVE-2025-29040 is a critical-severity OS Command Injection (CWE-78) vulnerability in Dlink Dir-823X Firmware. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked in the top 32% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2025-29040 is an OS command injection vulnerability (CWE-78) in D-Link DIR 823x devices running firmware version 240802. The flaw resides in the handling of the target_addr key value passed to the function at address 0x41737c and carries a CVSS 3.1 base score of 9.8.

Unauthenticated attackers with network access can supply a malicious target_addr value to execute arbitrary code on the device without user interaction, resulting in full control over confidentiality, integrity, and availability.

D-Link publishes a security bulletin at https://www.dlink.com/en/security-bulletin/ while public proof-of-concept repositories demonstrate the injection via the diag_ping endpoint.

The EPSS score rose from a lower baseline to a peak of 0.0879 on 2026-06-04 before receding to the current value of 0.0476, indicating a period of increased exploitation interest after disclosure.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

An issue in dlink DIR 823x 240802 allows a remote attacker to execute arbitrary code via the target_addr key value and the function 0x41737c

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
T1059.003 Windows Command Shell Execution
Adversaries may abuse the Windows command shell for execution.
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
T1059.001 PowerShell Execution
Adversaries may abuse PowerShell commands and scripts for execution.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-29042Same product: Dlink Dir-823X
CVE-2025-29041Same product: Dlink Dir-823X
CVE-2025-29043Same product: Dlink Dir-823X
CVE-2026-1544Same product: Dlink Dir-823X
CVE-2026-2129Same product: Dlink Dir-823X
CVE-2026-2120Same product: Dlink Dir-823X
CVE-2026-2175Same product: Dlink Dir-823X
CVE-2026-2063Same product: Dlink Dir-823X
CVE-2026-2084Same product: Dlink Dir-823X
CVE-2026-2157Same product: Dlink Dir-823X

Affected Assets

dlink
dir-823x firmware
240802

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V1.2.5
  • V1.2.8
  • V15.2.5

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation can discover missing or incorrect command sanitization during development.

Input validation directly neutralizes or rejects special characters that would otherwise alter OS command structure.

Least privilege reduces the permissions available to any process that could be subverted by injected commands.

Least functionality restricts available OS commands and interpreters, limiting the blast radius of injection.

Secure engineering principles require proper neutralization of untrusted input before command construction.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

PR.PS-06's SDLC practices directly require secure coding and input handling that blocks command-injection defects, yet the single broad outcome leaves many specific neutralization vectors and verification gaps unaddressed.

PR.PS-02 partial match
prevents

Routine patching/maintenance can remediate known command-injection CVEs in dependencies (partial forward) but does nothing to stop developers from introducing improper neutralization in custom code (none reverse).

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing and code review target insecure use of operating-system command interfaces, catching command-injection flaws introduced during development.

References