Cyber Resilience

CVE-2024-41338

Memory Safety in Draytek Vigor165 Firmware ≤ 4.2.6

Published
27 February 2025
Modified
05 July 2026
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0044 36th percentile
Risk Priority 57 floored blend · peak EPSS

Summary

CVE-2024-41338 is a high-severity NULL Pointer Dereference (CWE-476) vulnerability in Draytek Vigor165 Firmware. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Endpoint Denial of Service (T1499); ranked at the 36th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-15 (Development Process, Standards, and Tools) — 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-2024-41338 is a NULL pointer dereference vulnerability (CWE-476) affecting multiple Draytek Vigor router models running firmware versions prior to specified patches, including Vigor 165/166 before v4.2.6, Vigor 2620/LTE200 before v3.9.8.8, Vigor 2860/2925 before v3.9.7, Vigor 2862/2926 before v3.9.9.4, Vigor 2133/2762/2832 before v3.9.8, Vigor 2135/2765/2766 before v4.4.5.1, Vigor 2865/2866/2927 before v4.4.5.3, Vigor 2962/3910 before v4.3.2.7, Vigor 3912 before v4.3.5.2, and Vigor 2925 up to v3.9.6. The issue occurs in the processing of DHCP requests, with a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

The vulnerability can be exploited by unauthenticated attackers with network access, requiring low complexity and no user interaction. By sending a specially crafted DHCP request to the device, an attacker can trigger the NULL pointer dereference, causing a Denial of Service that disrupts device availability, such as crashing the router and halting network services.

Advisories recommend updating affected Draytek Vigor devices to the patched firmware versions listed in the CVE description or later. Further details on mitigations and patches are available from the vendor at http://draytek.com and the Faraday security advisory at https://medium.com/faraday/advisory-multiple-vulnerabilities-affecting-draytek-routers-78a6cb8b3946.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

A NULL pointer dereference in Draytek devices Vigor 165/166 prior to v4.2.6 , Vigor 2620/LTE200 prior to v3.9.8.8, Vigor 2860/2925 prior to v3.9.7, Vigor 2862/2926 prior to v3.9.9.4, Vigor 2133/2762/2832 prior to v3.9.8, Vigor 2135/2765/2766 prior to v4.4.5.1, Vigor 2865/2866/2927…

more

prior to v4.4.5.3, Vigor 2962/3910 prior to v4.3.2.7, Vigor 3912 prior to v4.3.5.2, and Vigor 2925 up to v3.9.6 allows attackers to cause a Denial of Service (DoS) via a crafted DHCP request.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
T1489 Service Stop Impact
Adversaries may stop or disable services on a system to render those services unavailable to legitimate users.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-41339Same product: Draytek Vigor165
CVE-2024-41340Same product: Draytek Vigor165
CVE-2024-41334Same product: Draytek Vigor165
CVE-2024-41592Same product: Draytek Vigor165
CVE-2024-41593Same product: Draytek Vigor165
CVE-2024-41591Same product: Draytek Vigor165
CVE-2024-41594Same product: Draytek Vigor165
CVE-2024-41596Same product: Draytek Vigor165
CVE-2024-41590Same product: Draytek Vigor165
CVE-2024-41588Same product: Draytek Vigor165

Affected Assets

draytek
vigor165 firmware
≤ 4.2.6
draytek
vigor166 firmware
≤ 4.2.6
draytek
vigor2620 firmware
≤ 3.9.8.8
draytek
vigorlte200 firmware
≤ 3.9.8.8
draytek
vigor2860 firmware
≤ 3.9.7
draytek
vigor2925 firmware
≤ 3.9.7
draytek
vigor2862 firmware
≤ 3.9.9.4
draytek
vigor2926 firmware
≤ 3.9.9.4
draytek
vigor2133 firmware
≤ 3.9.8
draytek
vigor2762 firmware
≤ 3.9.8
+10 more product configuration(s) — see NVD for full list

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation (including static analysis) directly finds null-dereference bugs before deployment.

Documented development standards and tools can enforce null-safety rules and safe pointer usage.

Engineering principles can mandate defensive coding such as explicit null checks before dereference.

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 (static analysis, code review, safe coding standards) directly prevent NULL dereference bugs during development.

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 can detect NULL dereference defects before release.

prevents

Secure SDLC mandates defensive coding practices that can prevent NULL dereferences.

prevents

Application security requirements can specify input validation and pointer-safety rules.

prevents

Secure architecture principles encourage defensive design that avoids unsafe pointer use.

prevents

Secure coding standards directly require NULL-pointer checks and safe dereference patterns.

References