CVE-2026-36610
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 · uneditedMercusys AC12G (EU) V1 with firmware AC12G(EU)_V1_200909 transmits DDNS credentials over plaintext HTTP with only Base64 encoding. The firmware contains no TLS implementation, allowing man-in-the-middle interception of DDNS service credentials.
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 confidenceThe Mercusys AC12G (EU) V1 router firmware AC12G(EU)_V1_200909 transmits DDNS service credentials using only Base64 encoding over plaintext HTTP, with no TLS implementation. This allows network-adjacent attackers to intercept DDNS credentials via man-in-the-middle attacks.
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
- High
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
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 checksWork through these to decide whether this CVE applies to you.
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Identify the router modelCheck the physical router label or log into the web admin interface to confirm the device is a Mercusys AC12GAffected if The device is a Mercusys AC12G router
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Check the firmware versionAccess the router admin panel (typically at 192.168.0.1 or 192.168.1.1), navigate to System or Firmware settings, and record the installed firmware version. Compare this against any available firmware release notes from Mercusys.Affected if The firmware version exists and the device is confirmed as AC12G (no specific vulnerable version range was provided, so treat all versions as potentially affected)
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Verify DDNS feature is configuredIn the router admin interface, navigate to the DDNS settings section (usually under Advanced or Network settings). Check if a DDNS provider is configured and enabled.Affected if DDNS is enabled and configured with a provider (the vulnerability only affects systems using the DDNS feature)
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Confirm DDNS credentials are sent over plaintext HTTPInspect the DDNS configuration page to determine if the connection uses HTTP (not HTTPS). If the settings page shows an HTTP URL or does not indicate HTTPS/TLS is used for the DDNS update, the credentials are being transmitted in plaintext.Affected if The DDNS update URL uses HTTP protocol rather than HTTPS, indicating credentials are transmitted without TLS encryption
A user is affected if they own a Mercusys AC12G router with DDNS enabled and the DDNS provider communication occurs over HTTP rather than HTTPS, exposing Base64-encoded credentials in plaintext.
Generated from the published advisory. Verify against your own configuration.
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 dataContact Mercusys for a firmware update implementing TLS for DDNS; if unavailable, replace with a router that supports encrypted DDNS transmission.
- Consultation3.0 h
- Implementation3.0 h
- Testing2.0 h
- Review / QA1.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-36610 — 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 sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-36610 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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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.
- 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