Cyber Resilience

CVE-2026-24110

Memory Safety in Tenda W20E Firmware 15.11.0.6

Public PoCMemory Safety
Published
02 March 2026
Modified
03 March 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 0.0043 35th percentile
Risk Priority 71 floored blend · peak EPSS

Summary

CVE-2026-24110 is a critical-severity Classic Buffer Overflow (CWE-120) vulnerability in Tenda W20E Firmware. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 35th percentile by exploit likelihood (below the median); 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-2026-24110 is a buffer overflow vulnerability (CWE-120) discovered in Tenda W20E router firmware version V4.0br_V15.11.0.6. The flaw occurs when attackers send overly long `addDhcpRules` data, which is processed by the `addDhcpRule` function via the command `ret = sscanf(pRule, " %d\t%[^\t]\t%[^\n\r\t]", &dhcpsIndex, dhcpsIP, dhcpsMac);`. Due to the absence of size validation, this can overflow fixed-size buffers for `dhcpsIndex`, `dhcpsIP`, and `dhcpsMac`.

The vulnerability has a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating it is exploitable remotely over the network by unauthenticated attackers with low complexity and no user interaction required. Exploitation allows attackers to achieve high impacts on confidentiality, integrity, and availability, potentially enabling arbitrary code execution or full device compromise through the buffer overflows.

Advisories and mitigation guidance are provided by Tenda at https://www.tenda.com.cn/material/show/2707 and in a CVE report on GitHub at https://github.com/akuma-QAQ/CVEreport/tree/main/D-link/CVE-2026-24110. Security practitioners should review these resources for available patches, firmware updates, or recommended workarounds.

EU & UK References

Vulnerability Data

An issue was discovered in Tenda W20E V4.0br_V15.11.0.6. Attackers may send overly long `addDhcpRules` data. When these rules enter the `addDhcpRule` function and are processed by `ret = sscanf(pRule, " %d\t%[^\t]\t%[^\n\r\t]", &dhcpsIndex, dhcpsIP, dhcpsMac);`, the lack of size validation for…

more

the rules could lead to buffer overflows in `dhcpsIndex`, `dhcpsIP`, and `dhcpsMac`.

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.
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-2026-24114Same product: Tenda W20E
CVE-2026-24112Same product: Tenda W20E
CVE-2026-24115Same product: Tenda W20E
CVE-2026-24113Same product: Tenda W20E
CVE-2026-24108Same product: Tenda W20E
CVE-2026-24111Same product: Tenda W20E
CVE-2026-24109Same product: Tenda W20E
CVE-2024-3874Same product: Tenda W20E
CVE-2023-26805Same product: Tenda W20E
CVE-2023-26806Same product: Tenda W20E

Affected Assets

tenda
w20e firmware
15.11.0.6

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)
  • V5.2.1

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and analysis can find missing size checks before deployment.

Input validation directly enforces size checks before buffer copies.

Engineering principles require bounds checking and safe buffer handling in design.

Memory protection limits the impact of an overflow once it occurs.

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 development practices directly enforce bounds checking and input validation that prevent classic buffer overflows.

ID.RA-01 partial match
prevents

Vulnerability identification processes such as code review or scanning detect classic buffer overflows before exploitation.

PR.PS-02 partial match
prevents

Routine patching replaces vulnerable code containing unchecked buffer copies with corrected versions.

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.

prevents

Secure coding directly requires bounds-checked memory operations, addressing the root cause of CWE-120.

finds

Security testing in development and acceptance can detect buffer overflows through fuzzing and static analysis, though it does not prevent them at the source.

prevents

Secure development life cycle mandates processes that can include input validation and bounds checking to prevent buffer overflows.

prevents

Application security requirements can specify input-size validation and safe buffer handling to mitigate classic buffer overflows.

prevents

Secure system architecture and engineering principles promote defensive coding patterns that reduce the likelihood of unchecked buffer copies.

References