Cyber Resilience

CVE-2026-4534

Memory Safety in Tenda Fh451 Firmware 1.0.0.9

Public PoCMemory Safety
Published
22 March 2026
Modified
03 April 2026
Patch / advisory
CVSS Score v4 7.4
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/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 0.0063 47th percentile
Risk Priority 37 floored blend · peak EPSS

Summary

CVE-2026-4534 is a high-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Tenda Fh451 Firmware. Its CVSS base score is 7.4 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 47th 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-2026-4534 is a stack-based buffer overflow vulnerability affecting Tenda FH451 router firmware version 1.0.0.9. The issue resides in the formWrlExtraSet function of the /goform/WrlExtraSet file, where manipulation of the GO argument triggers the overflow. Published on 2026-03-22, it is associated with CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) and CWE-121 (Stack-based Buffer Overflow).

The vulnerability carries a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H), indicating network accessibility, low attack complexity, and exploitation possible by low-privileged remote users without user interaction. Attackers can initiate the exploit remotely, potentially achieving high impacts on confidentiality, integrity, and availability, such as arbitrary code execution.

Advisories and references, including a GitHub repository at https://github.com/Litengzheng/vul_db/blob/main/FH451/vul_41/README.md containing a published exploit, VulDB entries at https://vuldb.com/?ctiid.352322, https://vuldb.com/?id.352322, and https://vuldb.com/?submit.774342, and the vendor site at https://www.tenda.com.cn/, provide further details. The exploit has been published and may be used, warranting immediate review of these sources for mitigation steps.

EU & UK References

Vulnerability Data

A flaw has been found in Tenda FH451 1.0.0.9. This affects the function formWrlExtraSet of the file /goform/WrlExtraSet. This manipulation of the argument GO causes stack-based buffer overflow. The attack can be initiated remotely. The exploit has been published and…

more

may be used.

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.
T1055 Process Injection Stealth
Adversaries may inject code into processes in order to evade process-based defenses as well as possibly elevate privileges.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-7805Same product: Tenda Fh451
CVE-2026-3677Same product: Tenda Fh451
CVE-2025-7795Same product: Tenda Fh451
CVE-2025-7505Same product: Tenda Fh451
CVE-2025-7794Same product: Tenda Fh451
CVE-2026-4535Same product: Tenda Fh451
CVE-2025-7434Same product: Tenda Fh451
CVE-2025-7793Same product: Tenda Fh451
CVE-2025-7853Same product: Tenda Fh451
CVE-2025-7855Same product: Tenda Fh451

Affected Assets

tenda
fh451 firmware
1.0.0.9

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.

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.

none

Change-management gates can enforce security reviews that catch buffer issues.

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