Cyber Resilience

CVE-2025-5622

Memory Safety in Dlink Dir-816 Firmware 1.10cnb05

Public PoCMemory Safety
Published
05 June 2025
Modified
17 June 2026
Patch / advisory
CVSS Score v4 9.3
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS Score 0.021 80th percentile
Risk Priority 49 floored blend · peak EPSS

Summary

CVE-2025-5622 is a critical-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Dlink Dir-816 Firmware. Its CVSS base score is 9.3 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 20% 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.

A vulnerability classified as critical was identified in the D-Link DIR-816 1.10CNB05 router. It resides in the wirelessApcli_5g function of the /goform/wirelessApcli_5g endpoint, where improper handling of the apcli_mode_5g, apcli_enc_5g, and apcli_default_key_5g arguments triggers a stack-based buffer overflow. The issue maps to CWE-119, CWE-121, and CWE-787 and carries a CVSS 4.0 score of 9.3 reflecting network-accessible attack conditions without authentication or user interaction.

An unauthenticated remote attacker can supply crafted input to the affected form handler and execute arbitrary code or crash the device, resulting in full compromise of confidentiality, integrity, and availability. Public exploit code has already been released, and the flaw is restricted to an end-of-life product line that receives no further vendor support.

The listed references point to a detailed proof-of-concept on GitHub, multiple VulDB entries, and the vendor’s site, but contain no remediation guidance or patches because the hardware is unsupported. The associated EPSS score has remained flat at 0.0109 with no material rise since disclosure.

EU & UK References

Vulnerability Data

A vulnerability was found in D-Link DIR-816 1.10CNB05 and classified as critical. Affected by this issue is the function wirelessApcli_5g of the file /goform/wirelessApcli_5g. The manipulation of the argument apcli_mode_5g/apcli_enc_5g/apcli_default_key_5g leads to stack-based buffer overflow. The attack may be launched…

more

remotely. The exploit has been disclosed to the public and may be used. This vulnerability only affects products that are no longer supported by the maintainer.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
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.
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
T1211 Exploitation for Stealth Stealth
Adversaries may exploit vulnerabilities to evade detection by hiding activity, suppressing logging, or operating within trusted or unmonitored components.
T1212 Exploitation for Credential Access Credential Access
Adversaries may exploit software vulnerabilities in an attempt to collect credentials.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-4183Same product: Dlink Dir-816
CVE-2026-4181Same product: Dlink Dir-816
CVE-2025-5630Same product: Dlink Dir-816
CVE-2025-5623Same product: Dlink Dir-816
CVE-2025-5624Same product: Dlink Dir-816
CVE-2026-4184Same product: Dlink Dir-816
CVE-2026-4182Same product: Dlink Dir-816
CVE-2025-61577Same product: Dlink Dir-816
CVE-2025-60679Same product: Dlink Dir-816
CVE-2025-4843Same vendor: Dlink

Affected Assets

dlink
dir-816 firmware
1.10cnb05

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 2 hardening rules · 2 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V17.3.2

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and analysis can discover stack-buffer overflows before deployment.

Input validation directly stops untrusted data from exceeding stack buffer bounds.

Memory-protection mechanisms limit the ability to execute injected code after a stack overflow.

Requiring documented secure-development standards and tools can mandate bounds-checked coding practices that avoid the weakness.

Secure engineering principles require memory-safe design and coding that structurally avoids buffer-boundary violations.

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

Secure SDLC practices (bounds checking, safe APIs, reviews) directly prevent this class of flaw.

ID.RA-01 partial match
prevents

Vulnerability scanning and code analysis directly surface buffer-boundary flaws.

ID.RA-08 partial match
prevents

Receiving and triaging vulnerability disclosures commonly includes buffer-related reports.

PR.AT-02 partial match
prevents

Developer training on secure coding reduces introduction of memory-buffer errors.

PR.PS-02 partial match
prevents

Patching replaces vulnerable code containing buffer-boundary defects.

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 in development catches out-of-bounds accesses before release, covering most instances of the weakness.

prevents

Secure development lifecycle mandates memory-safety practices that directly prevent buffer-boundary violations.

prevents

Application security requirements can specify memory-safety rules, but do not prescribe implementation details.

prevents

Secure architecture and engineering principles include memory-safe design patterns that mitigate buffer overflows.

prevents

Secure coding standards explicitly forbid unsafe buffer operations, directly eliminating CWE-119.

prevents

Change management can enforce review gates that catch unsafe memory operations before deployment.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).

Oracle Linux 8 (1 rule)
  • V-248594 OL 8 must implement address space layout randomization (ASLR) to protect its memory from unauthorized code execution. prevents CWE-121
Oracle Linux 9 (1 rule)
  • V-271452 OL 9 must use a Linux Security Module configured to enforce limits on system services. prevents CWE-121

References