Cyber Posture

CVE-2025-25635

HighPublic PoC

Published: 28 February 2025

Published
28 February 2025
Modified
02 October 2025
KEV Added
Patch
CVSS Score 8.0 CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0008 24.2th percentile
Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-25635 is a high-severity Classic Buffer Overflow (CWE-120) vulnerability in Totolink A3002R Firmware. Its CVSS base score is 8.0 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 24.2th 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 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

Directly requires validation of inputs like the pppoe_dns1 parameter to prevent buffer overflows from improper input handling in the formIpv6Setup interface.

prevent

Mandates timely identification, reporting, and correction of the specific buffer overflow flaw in the /bin/boa web server component.

prevent

Provides memory protection mechanisms like address space layout randomization or non-executable stacks to mitigate exploitation of the buffer overflow for 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 the public-facing web interface (/bin/boa formIpv6Setup pppoe_dns1 parameter) enables remote code execution via exploitation of a public-facing application.

NVD Description

TOTOlink A3002R V1.1.1-B20200824.0128 contains a buffer overflow vulnerability. The vulnerability arises from the improper input validation of the pppoe_dns1 parameter in the formIpv6Setup interface of /bin/boa.

Deeper analysisAI

CVE-2025-25635 is a buffer overflow vulnerability (CWE-120) affecting the TOTOlink A3002R router in version V1.1.1-B20200824.0128. The issue arises from improper input validation of the pppoe_dns1 parameter in the formIpv6Setup interface, which is handled by the /bin/boa web server component. Published on 2025-02-28, it carries a CVSS v3.1 base score of 8.0 (AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).

An adjacent network attacker (AV:A) with low privileges (PR:L), such as an authenticated user, can exploit the vulnerability with low attack complexity (AC:L) and no user interaction required (UI:N). Successful exploitation allows high-impact consequences, including unauthorized disclosure of information, modification of data, and denial of service (C:H/I:H/A:H), likely enabling remote code execution on the affected device.

A proof-of-concept and technical details are documented in a GitHub repository at https://github.com/SunnyYANGyaya/cuicuishark-sheep-fishIOT/blob/main/ToTolink/TOTOLINK-A3002R-formIpv6Setup-pppoe_dns1.md. No official vendor advisories or patches are referenced in the CVE details.

Details

CWE(s)

Affected Products

totolink
a3002r firmware
1.1.1-b20200824.0128

CVEs Like This One

CVE-2025-25609Same product: Totolink A3002R
CVE-2025-25610Same product: Totolink A3002R
CVE-2025-25579Same product: Totolink A3002R
CVE-2025-55591Same product: Totolink A3002R
CVE-2025-67186Same vendor: Totolink
CVE-2026-31027Same vendor: Totolink
CVE-2025-67188Same vendor: Totolink
CVE-2025-51630Same vendor: Totolink
CVE-2025-9780Same vendor: Totolink
CVE-2026-1157Same vendor: Totolink

References