Wcr 300 FirmwareOperating system · Buffalo

CVE-2022-40966

HIGH · 8.8 CVSS v3.1 Published 2022-12-07
Fix available
A fix is available. Upgrade to after 2.96 or later.
See remediation →
93/100
Remediation priority · Urgent
No privileges Zero-click Patch available

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
Authentication bypass vulnerability in multiple Buffalo network devices allows a network-adjacent attacker to bypass authentication and access the device. The affected products/versions are as follows: WCR-300 firmware Ver. 1.87 and earlier, WHR-HP-G300N firmware Ver. 2.00 and earlier, WHR-HP-GN firmware Ver. 1.87 and earlier, WPL-05G300 firmware Ver. 1.88 and earlier, WRM-D2133HP firmware Ver. 2.85 and earlier, WRM-D2133HS firmware Ver. 2.96 and earlier, WTR-M2133HP firmware Ver. 2.85 and earlier, WTR-M2133HS firmware Ver. 2.96 and earlier, WXR-1900DHP firmware Ver. 2.50 and earlier, WXR-1900DHP2 firmware Ver. 2.59 and earlier, WXR-1900DHP3 firmware Ver. 2.63 and earlier, WXR-5950AX12 firmware Ver. 3.40 and earlier, WXR-6000AX12B firmware Ver. 3.40 and earlier, WXR-6000AX12S firmware Ver. 3.40 and earlier, WZR-300HP firmware Ver. 2.00 and earlier, WZR-450HP firmware Ver. 2.00 and earlier, WZR-600DHP firmware Ver. 2.00 and earlier, WZR-900DHP firmware Ver. 1.15 and earlier, WZR-1750DHP2 firmware Ver. 2.31 and earlier, WZR-HP-AG300H firmware Ver. 1.76 and earlier, WZR-HP-G302H firmware Ver. 1.86 and earlier, WEM-1266 firmware Ver. 2.85 and earlier, WEM-1266WP firmware Ver. 2.85 and earlier, WLAE-AG300N firmware Ver. 1.86 and earlier, FS-600DHP firmware Ver. 3.40 and earlier, FS-G300N firmware Ver. 3.14 and earlier, FS-HP-G300N firmware Ver. 3.33 and earlier, FS-R600DHP firmware Ver. 3.40 and earlier, BHR-4GRV firmware Ver. 2.00 and earlier, DWR-HP-G300NH firmware Ver. 1.84 and earlier, DWR-PG firmware Ver. 1.83 and earlier, HW-450HP-ZWE firmware Ver. 2.00 and earlier, WER-A54G54 firmware Ver. 1.43 and earlier, WER-AG54 firmware Ver. 1.43 and earlier, WER-AM54G54 firmware Ver. 1.43 and earlier, WER-AMG54 firmware Ver. 1.43 and earlier, WHR-300 firmware Ver. 2.00 and earlier, WHR-300HP firmware Ver. 2.00 and earlier, WHR-AM54G54 firmware Ver. 1.43 and earlier, WHR-AMG54 firmware Ver. 1.43 and earlier, WHR-AMPG firmware Ver. 1.52 and earlier, WHR-G firmware Ver. 1.49 and earlier, WHR-G300N firmware Ver. 1.65 and earlier, WHR-G301N firmware Ver. 1.87 and earlier, WHR-G54S firmware Ver. 1.43 and earlier, WHR-G54S-NI firmware Ver. 1.24 and earlier, WHR-HP-AMPG firmware Ver. 1.43 and earlier, WHR-HP-G firmware Ver. 1.49 and earlier, WHR-HP-G54 firmware Ver. 1.43 and earlier, WLI-H4-D600 firmware Ver. 1.88 and earlier, WS024BF firmware Ver. 1.60 and earlier, WS024BF-NW firmware Ver. 1.60 and earlier, WXR-1750DHP firmware Ver. 2.60 and earlier, WXR-1750DHP2 firmware Ver. 2.60 and earlier, WZR-1166DHP firmware Ver. 2.18 and earlier, WZR-1166DHP2 firmware Ver. 2.18 and earlier, WZR-1750DHP firmware Ver. 2.30 and earlier, WZR2-G300N firmware Ver. 1.55 and earlier, WZR-450HP-CWT firmware Ver. 2.00 and earlier, WZR-450HP-UB firmware Ver. 2.00 and earlier, WZR-600DHP2 firmware Ver. 1.15 and earlier, WZR-600DHP3 firmware Ver. 2.19 and earlier, WZR-900DHP2 firmware Ver. 2.19 and earlier, WZR-AGL300NH firmware Ver. 1.55 and earlier, WZR-AMPG144NH firmware Ver. 1.49 and earlier, WZR-AMPG300NH firmware Ver. 1.51 and earlier, WZR-D1100H firmware Ver. 2.00 and earlier, WZR-G144N firmware Ver. 1.48 and earlier, WZR-G144NH firmware Ver. 1.48 and earlier, WZR-HP-G300NH firmware Ver. 1.84 and earlier, WZR-HP-G301NH firmware Ver. 1.84 and earlier, WZR-HP-G450H firmware Ver. 1.90 and earlier, WZR-S1750DHP firmware Ver. 2.32 and earlier, WZR-S600DHP firmware Ver. 2.19 and earlier, and WZR-S900DHP firmware Ver. 2.19 and earlier.

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
How this class of weakness works · CWE-287

The mechanism that verifies who a user is can be side-stepped or fooled, letting an attacker act as someone they're not. Everything built on top of that identity then becomes untrustworthy. Fixing it means hardening the full authentication flow, including edge cases, tokens, and secondary paths.

General guidance for the improper authentication class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →

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
Wcr 300 FirmwareOperating system
Affected:<= 1.87
Whr Hp G300n FirmwareOperating system
Affected:<= 2.00
Whr Hp Gn FirmwareOperating system
Affected:<= 1.87
Wpl 05g300 FirmwareOperating system
Affected:<= 1.88
Wrm D2133hp FirmwareOperating system
Affected:<= 2.85
Wrm D2133hs FirmwareOperating system
Affected:<= 2.96
Wtr M2133hp FirmwareOperating system
Affected:<= 2.85
Wtr M2133hs FirmwareOperating system
Affected:<= 2.96

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
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

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

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
Upgrade available Upgrade to a release after 2.96
Vendor patch www.buffalo.jp →
Recommended fix High confidence

Latest firmware version available from Buffalo's support website (vendor security advisory released October 2022)

  1. 1. Identify the exact Buffalo device model number from the affected product list.
  2. 2. Access the device's web management interface and navigate to the Administration or System settings.
  3. 3. Locate and record the current firmware version displayed.
  4. 4. Visit Buffalo's official support page at https://www.buffalo.jp/support/ and search for the specific device model.
  5. 5. Download the latest firmware version available for the device (the fixed version is any release newer than the vulnerable versions listed).
  6. 6. In the device's web management interface, locate the Firmware Update section.
  7. 7. Upload and apply the downloaded firmware update file.
  8. 8. After the update completes, verify the new firmware version is displayed and confirm the device is functioning normally.
Caveat Firmware updates on network devices may temporarily interrupt connectivity; ensure power stability during the update process

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

We can identify the exact fixed release, upgrade, and verify it in staging — typical engagement from $1,950. Get the upgrade done

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2022-40966 — 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-2022-40966 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