A3002r FirmwareOperating system · Totolink

CVE-2025-4731

HIGH · 8.8 CVSS v3.1 Published 2025-05-16
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
94/100
Remediation priority · Urgent
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A vulnerability classified as critical has been found in TOTOLINK A3002R and A3002RU 3.0.0-B20230809.1615. This affects an unknown part of the file /boafrm/formPortFw of the component HTTP POST Request Handler. The manipulation of the argument service_type/ip_subnet leads to buffer overflow. It is possible to initiate the attack remotely. The exploit has been disclosed to the public and may be used.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Buffer overflow vulnerability in TOTOLINK A3002R/A3002RU routers (firmware 3.0.0-B20230809.1615) in the HTTP POST request handler for /boafrm/formPortFw. The service_type/ip_subnet argument is not properly bounds-checked, allowing an attacker to overflow a buffer via crafted HTTP POST requests. The vulnerability is remotely exploitable and a public exploit exists.

MitigationApply vendor firmware update when available; until then, disable the port forwarding feature via the router admin interface, restrict administrative access to trusted IPs only, or replace the device with a supported model.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
A3002r FirmwareOperating system
Affected:= 3.0.0-b20230809.1615
A3002ru FirmwareOperating system
Affected:= 3.0.0-b20230809.1615

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify router model
    Access the router admin interface (typically at 192.168.1.1) and check the device information page, or check the device label for model number A3002R or A3002RU
    Affected if Model is TOTOLINK A3002R or A3002RU
  2. Check installed firmware version
    In the router admin interface, navigate to System Status or Firmware version section, or check via telnet/SSH if available. Compare the firmware version to 3.0.0-B20230809.1615
    Affected if Firmware version is exactly 3.0.0-B20230809.1615
  3. Verify port forwarding feature accessibility
    Log into the router admin interface and navigate to the port forwarding settings page (usually under Advanced or NAT settings). Attempt to access /boafrm/formPortFw endpoint if you have direct access
    Affected if Port forwarding feature is accessible and enabled on the device
  4. Check administrative access exposure
    Determine if the router admin interface is exposed to the WAN/internet by checking port forwarding rules, firewall settings, or by attempting to access the router IP from an external network
    Affected if Router admin interface is accessible from WAN/internet

Device is affected if it is a TOTOLINK A3002R or A3002RU router running firmware version 3.0.0-B20230809.1615 with the port forwarding feature accessible.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply vendor firmware update when available; until then, disable the port forwarding feature via the router admin interface, restrict administrative access to trusted IPs only, or replace the device with a supported model.

Fix this in A3002r Firmware Scoped from the published advisory
  • Consultation3.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
8.0 hours of engineering $1,440
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,304.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2025-4731 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-4731 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data