Cyber Resilience

CVE-2026-4254

Memory Safety in Tenda Ac8 Firmware ≤ 16.03.50.11

Public PoCMemory Safety
Published
16 March 2026
Modified
20 March 2026
Patch / advisory
CVSS Score v4 8.9
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: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 0.0089 56th percentile
Risk Priority 46 floored blend · peak EPSS

Summary

CVE-2026-4254 is a high-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Tenda Ac8 Firmware. Its CVSS base score is 8.9 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 44% 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-2026-4254 is a stack-based buffer overflow vulnerability affecting Tenda AC8 router firmware versions up to 16.03.50.11. The flaw exists in the doSystemCmd function of the /goform/SysToolChangePwd component within the HTTP endpoint, where manipulation of the local_2c argument triggers the overflow. It is classified under CWEs 119, 121, and 787.

The vulnerability enables remote exploitation by unauthenticated attackers (PR:N) with low attack complexity (AC:L) and no user interaction (UI:N). Successful exploitation can result in high impacts to confidentiality, integrity, and availability (C:H/I:H/A:H), yielding a CVSS v3.1 base score of 9.8.

Advisories and reports are documented on VulDB (ctiid.351212, id.351212, submit.771773) and a GitHub repository detailing the CVE, including a publicly available exploit. The Tenda manufacturer's site (tenda.com.cn) is referenced, though specific patch details are not outlined in the disclosures.

The exploit has been made publicly available, heightening the potential for real-world attacks on vulnerable devices.

EU & UK References

Vulnerability Data

A weakness has been identified in Tenda AC8 up to 16.03.50.11. This vulnerability affects the function doSystemCmd of the file /goform/SysToolChangePwd of the component HTTP Endpoint. This manipulation of the argument local_2c causes stack-based buffer overflow. The attack can be…

more

initiated remotely. The exploit has been made available to the public and could be used for attacks.

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-2025-1853Same product: Tenda Ac8
CVE-2024-11745Same product: Tenda Ac8
CVE-2024-4064Same product: Tenda Ac8
CVE-2024-4066Same product: Tenda Ac8
CVE-2024-4065Same product: Tenda Ac8
CVE-2023-4744Same product: Tenda Ac8
CVE-2026-3044Same product: Tenda Ac8
CVE-2025-5798Same product: Tenda Ac8
CVE-2025-5799Same product: Tenda Ac8
CVE-2025-4368Same product: Tenda Ac8

Affected Assets

tenda
ac8 firmware
≤ 16.03.50.11

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