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Memory Buffer Bounds ErrorWeakness · CWE-119

CVE-2026-9399

HIGH · 8.8 CVSS v3.1 Published 2026-05-24
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 was detected in Edimax BR-6675nD 1.12. This vulnerability affects the function formsetPPPoE of the file /goform/formsetPPPoE of the component POST Request Handler. Performing a manipulation of the argument pppUserName results in buffer overflow. It is possible to initiate the attack remotely. The exploit is now public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

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 · moderate confidence

Buffer overflow vulnerability in Edimax BR-6675nD 1.12 router's PPPoE configuration handler (formsetPPPoE function). The pppUserName parameter in POST requests to /goform/formsetPPPoE is not properly validated for length, allowing remote attackers to overflow a buffer and potentially execute arbitrary code.

MitigationNo vendor patch available due to lack of vendor response. Mitigate by restricting network access to the router's management interface, disabling remote administration if enabled, and monitoring for exploitation attempts. Replace end-of-life device if network isolation is not feasible.

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

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. Confirm device model is Edimax BR-6675nD
    Access the router web interface and check the status or system information page for the exact model number, or inspect the device label/hardware itself
    Affected if The device is an Edimax BR-6675nD router (or any related variant in the same product family)
  2. Verify router web interface is accessible
    Attempt to access the router's HTTP administration interface at the default gateway IP (commonly 192.168.1.1 or 192.168.2.1)
    Affected if The administrative web interface is reachable from the network (the vulnerability is exploitable via HTTP POST requests to /goform/formsetPPPoE)
  3. Check if PPPoE configuration interface exists
    Navigate to the router's WAN or Internet settings page and look for PPPoE configuration options (typically labeled PPPoE, DSL, or WAN Connection Type)
    Affected if PPPoE is available as a connection type option - the vulnerable formsetPPPoE function handles this feature
  4. Determine if PPPoE is currently configured
    Examine the PPPoE settings page to see if a username and password are currently saved for PPPoE connections
    Affected if PPPoE is enabled with saved credentials - the overflow occurs when processing the pppUserName parameter in the form submission

You are affected if you are using an Edimax BR-6675nD router with its web interface accessible and PPPoE configuration enabled, as the buffer overflow occurs in the formsetPPPoE handler when processing the PPPoE username field.

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.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

No vendor patch available due to lack of vendor response. Mitigate by restricting network access to the router's management interface, disabling remote administration if enabled, and monitoring for exploitation attempts. Replace end-of-life device if network isolation is not feasible.

Recommended fix High confidence

Replace with a currently supported router from a vendor that provides security updates

  1. Replace the Edimax BR-6675nD router with a currently supported model from a vendor that provides regular security firmware updates, as no patch is available for this vulnerability.
  2. If the device must remain in service temporarily, disable the PPPoE functionality if not required, though this does not eliminate the underlying buffer overflow vulnerability in the POST request handler.
Caveat Full hardware replacement required; legacy PPPoE-based ISP configurations may need to be reconfigured on new hardware

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed 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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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-2026-9399 in production — separate from our analysis above.

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