A702r FirmwareOperating system · Totolink

CVE-2025-4830

HIGH · 8.8 CVSS v3.1 Published 2025-05-17
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, which was classified as critical, has been found in TOTOLINK A702R, A3002R and A3002RU 3.0.0-B20230809.1615. Affected by this issue is some unknown functionality of the file /boafrm/formSysCmd of the component HTTP POST Request Handler. The manipulation of the argument submit-url leads to buffer overflow. The attack may be launched 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 A702R, A3002R, and A3002RU routers (firmware 3.0.0-B20230809.1615) in the HTTP POST handler for /boafrm/formSysCmd. The 'submit-url' argument is not properly bounds-checked, allowing remote attackers to overflow a buffer via crafted HTTP POST requests. Public exploit available.

MitigationApply vendor firmware update when available. If no update exists, disable the affected formSysCmd functionality via device administration interface, implement network segmentation to limit exposure, and monitor for unauthorized access attempts.

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
A702r FirmwareOperating system
Affected:= 3.0.0-b20230809.1615
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 web administration interface and locate the device information page, or use nmap or a browser to access the login page and check the model number displayed in the interface header or footer
    Affected if Router model is A702R, A3002R, or A3002RU
  2. Check firmware version
    In the router web interface, navigate to System Status or Device Info page and locate the firmware version field. Alternatively, inspect the HTTP response headers or the login page source for version strings
    Affected if Firmware version is exactly 3.0.0-B20230809.1615
  3. Verify vulnerable endpoint exists
    Send a crafted HTTP POST request to /boafrm/formSysCmd using curl or Burp Suite. Example: curl -X POST http://<router-ip>/boafrm/formSysCmd -d "submit-url=test"
    Affected if The endpoint responds with non-error status (indicating formSysCmd functionality is enabled and accessible)
  4. Confirm web interface accessibility
    Attempt to access the router login page at http://<router-ip>/ or check network exposure using nmap: nmap -p 80,443 <router-ip>
    Affected if The router web interface is reachable from the network being assessed (indicating the attack surface is present)

The environment is affected if the router model is A702R, A3002R, or A3002RU running firmware version 3.0.0-B20230809.1615 and the /boafrm/formSysCmd endpoint is accessible on the network.

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. If no update exists, disable the affected formSysCmd functionality via device administration interface, implement network segmentation to limit exposure, and monitor for unauthorized access attempts.

Fix this in A702r Firmware Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA1.0 h
10.0 hours of engineering $1,750
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Scan for this in your stack

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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-2025-4830 in production — separate from our analysis above.

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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
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  • Version or environment caveats, and links to real fixes
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