CyberSecBulletin
CVE-2026-32678NVD status: Analyzed

BUFFALO Wi-Fi router products: Authentication Bypass Using an Alternate Path or Channel

Published Updated By the CyberSecBulletin desk

CVE-2026-32678 is a high-severity authentication bypass using an alternate path or channel vulnerability in BUFFALO Wi-Fi router products from Buffalo, with a CVSS 4.0 base score of 8.7 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected BUFFALO Wi-Fi router products versions: See "References" section. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.38% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Wcr-1166dhpl Firmware to 1.01 or a later version.
  2. Update Wsr3600be4-kh Firmware to 6.02 or a later version.
  3. Update Wsr3600be4p Firmware to 5.02 or a later version.
  4. Read the advisory on buffalo.jp for workarounds and exact fixed builds.
  5. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
BUFFALOBUFFALO Wi-Fi router productsSee "References" sectionNot stated
BuffaloWzr-s900dhp FirmwareNot specified in the recordNot stated
BuffaloWcr-1166dhpl Firmwarebefore 1.011.01
BuffaloWsr3600be4-kh Firmwarebefore 6.026.02
BuffaloWsr3600be4p Firmwarebefore 5.025.02
BuffaloWxr-1750dhp Firmwarebefore 2.632.63
BuffaloWxr-1750dhp2 Firmwarebefore 2.632.63
BuffaloWxr18000be10p Firmwarebefore 5.035.03
BuffaloWxr-1900dhp Firmwarebefore 2.532.53
BuffaloWxr-1900dhp2 Firmwarebefore 2.622.62
BuffaloWxr-1900dhp3 Firmwarebefore 2.662.66
BuffaloWxr-5950ax12 Firmwarebefore 3.573.57
BuffaloWxr-6000ax12b Firmwarebefore 3.573.57
BuffaloWxr-6000ax12p Firmwarebefore 3.573.57
BuffaloWxr-6000ax12s Firmwarebefore 3.573.57
BuffaloWzr-1166dhp Firmwarebefore 2.202.20
BuffaloWzr-1166dhp2 Firmwarebefore 2.202.20
BuffaloWzr-1750dhp Firmwarebefore 2.322.32
BuffaloWzr-1750dhp2 Firmwarebefore 2.332.33
BuffaloWzr-s1750dhp Firmwarebefore 2.342.34
BuffaloWrm-d2133hp Firmwarebefore 3.013.01
BuffaloWrm-d2133hs Firmwarebefore 3.013.01
BuffaloWtr-m2133hp Firmwarebefore 3.013.01
BuffaloWtr-m2133hs Firmwarebefore 3.013.01
BuffaloWem-1266 Firmwarebefore 2.872.87

Version data comes from the organisation that assigned the CVE; 22 further products are omitted here. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Attack requirements
NoneThe attack does not depend on a particular deployment or configuration.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Confidentiality (vulnerable system)
NoneNo loss of confidentiality on the vulnerable system.
Integrity (vulnerable system)
HighSerious loss of integrity on the vulnerable system.
Availability (vulnerable system)
NoneNo loss of availability on the vulnerable system.
Confidentiality (other systems)
NoneNo loss of confidentiality on systems beyond the vulnerable one.
Integrity (other systems)
NoneNo loss of integrity on systems beyond the vulnerable one.
Availability (other systems)
NoneNo loss of availability on systems beyond the vulnerable one.

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. Scored by CNA (jpcert.or.jp).

Scoring systemScoreSeverityScored by
CVSS 4.08.7HighCNA (jpcert.or.jp)
CVSS 3.07.5HighCNA (jpcert.or.jp)

Official description

Authentication bypass issue exists in BUFFALO Wi-Fi router products, which may allow an attacker to alter critical configuration settings without authentication.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Authentication Bypass Using an Alternate Path or Channel

The product requires authentication, but the product has an alternate path or channel that does not require authentication.

How developers prevent this class of flaw

  • Funnel all access through a single choke point to simplify how users can access a resource. For every access, perform a check to determine if the user has permissions to access the resource.

More Authentication Bypass Using an Alternate Path or Channel vulnerabilities (CWE-288)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in BUFFALO Wi-Fi router products

All BUFFALO Wi-Fi router products vulnerabilities

Recent Authentication Bypass Using an Alternate Path or Channel vulnerabilities

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