Cyber Resilience

CVE-2025-10120

Memory Safety in Tenda Ac20 Firmware ≤ 16.03.08.12

Public PoCMemory Safety
Published
09 September 2025
Modified
10 September 2025
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 0.0083 54th percentile
Risk Priority 38 floored blend · peak EPSS

Summary

CVE-2025-10120 is a high-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Tenda Ac20 Firmware. Its CVSS base score is 7.4 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked in the top 46% 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-2025-10120 is a buffer overflow vulnerability in Tenda AC20 routers running firmware versions up to 16.03.08.12. The issue resides in the strcpy function within the /goform/GetParentControlInfo file, where manipulation of the "mac" argument triggers the overflow. Associated with CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) and CWE-120 (Buffer Copy without Checking Size of Input), it 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 high severity.

Remote attackers with low privileges can exploit this vulnerability over the network with low complexity and no user interaction required. Successful exploitation allows attackers to achieve high impacts on confidentiality, integrity, and availability, potentially leading to arbitrary code execution or system compromise on the affected router.

VulDB advisories (ctiid.323089, id.323089) document the issue, while a public proof-of-concept exploit is available on GitHub at cymiao1978/cve/blob/main/4.md and its #poc section. No vendor patches or specific mitigations are detailed in the provided references; security practitioners should monitor for firmware updates from Tenda.

The exploit is public and available for use, as noted in the CVE description published on 2025-09-09.

EU & UK References

Vulnerability Data

A vulnerability was detected in Tenda AC20 up to 16.03.08.12. The impacted element is the function strcpy of the file /goform/GetParentControlInfo. The manipulation of the argument mac results in buffer overflow. The attack may be performed from remote. The exploit…

more

is now public and 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.
T1055 Process Injection Stealth
Adversaries may inject code into processes in order to evade process-based defenses as well as possibly elevate privileges.
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-2025-11385Same product: Tenda Ac20
CVE-2025-15356Same product: Tenda Ac20
CVE-2025-8939Same product: Tenda Ac20
CVE-2025-8940Same product: Tenda Ac20
CVE-2025-10815Same product: Tenda Ac20
CVE-2025-13258Same product: Tenda Ac20
CVE-2025-14656Same product: Tenda Ac20
CVE-2025-8160Same product: Tenda Ac20
CVE-2025-9089Same product: Tenda Ac20
CVE-2025-9046Same product: Tenda Ac20

Affected Assets

tenda
ac20 firmware
≤ 16.03.08.12

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)
  • V17.3.2
  • 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.

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

Memory protection restricts exploitation impact of buffer overflows without eliminating the underlying coding flaw.

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.

prevents

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

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.

References