Cyber Posture

CVE-2025-9780

High

Published: 01 September 2025

Published
01 September 2025
Modified
04 September 2025
KEV Added
Patch
CVSS Score 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0029 52.8th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-9780 is a high-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Totolink A702R Firmware. Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 47.2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-2 (Flaw Remediation).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190). What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Flaw remediation directly addresses the buffer overflow in sub_419BE0 by applying vendor patches or updates to the TOTOLINK A702R firmware.

prevent

Information input validation enforces proper bounds checking and sanitization of the 'mac' argument in /boafrm/formIpQoS to prevent buffer overflow exploitation.

prevent

Memory protection mechanisms like ASLR and DEP mitigate successful exploitation of the buffer overflow for arbitrary code execution.

MITRE ATT&CK Enterprise TechniquesAI

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.
Why these techniques?

Buffer overflow in public web form (/boafrm/formIpQoS) on network device directly enables remote exploitation of a public-facing application for code execution.

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

A flaw has been found in TOTOLINK A702R 4.0.0-B20211108.1423. Affected by this issue is the function sub_419BE0 of the file /boafrm/formIpQoS. This manipulation of the argument mac causes buffer overflow. The attack can be initiated remotely. The exploit has been…

more

published and may be used.

Deeper analysisAI

CVE-2025-9780 is a buffer overflow vulnerability affecting the TOTOLINK A702R router on firmware version 4.0.0-B20211108.1423. The flaw exists in the function sub_419BE0 within the /boafrm/formIpQoS file, where manipulation of the 'mac' argument triggers the overflow. This issue, linked to CWE-119 and CWE-120, was published on 2025-09-01 and 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).

A remote attacker with low privileges can exploit this vulnerability over the network with low attack complexity and without requiring user interaction. Successful exploitation grants high impacts on confidentiality, integrity, and availability, potentially allowing arbitrary code execution or system compromise.

References include GitHub repositories from rew1X detailing the vulnerability and providing a proof-of-concept exploit, along with VulDB entries documenting the issue (ctiid.322082, id.322082, submit.640988). The published exploit indicates it may be actively usable by attackers.

Details

CWE(s)

Affected Products

totolink
a702r firmware
4.0.0-b20211108.1423

CVEs Like This One

CVE-2025-9783Same product: Totolink A702R
CVE-2025-9779Same product: Totolink A702R
CVE-2025-8139Same product: Totolink A702R
CVE-2025-8138Same product: Totolink A702R
CVE-2025-8136Same product: Totolink A702R
CVE-2025-9781Same product: Totolink A702R
CVE-2025-8137Same product: Totolink A702R
CVE-2025-8140Same product: Totolink A702R
CVE-2025-9782Same product: Totolink A702R
CVE-2025-9303Same vendor: Totolink

References