CVE-2026-33280: Hidden functionality issue exists in BUFFALO Wi-Fi router products, which may allow an attacker to gain access
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CRITICAL 9.8REMOTEUPGRADEUPGRADEUPGRADE
CVE-2026-33280 is a critical-severity flaw (CVSS 9.8) affecting wcr-1166dhpl firmware, wsr3600be4-kh firmware, wsr3600be4p firmware. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Hidden functionality issue exists in BUFFALO Wi-Fi router products, which may allow an attacker to gain access to the product’s debugging functionality, resulting in the execution of arbitrary OS commands.
Last updated 2026-10-26 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
Published CVE record published
Updated Record last modified
buffalo wcr-1166dhpl firmware UPGRADE
Affected: < 1.01
Fixed in: 1.01
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
buffalo wsr3600be4-kh firmware UPGRADE
Affected: < 6.02
Fixed in: 6.02
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
buffalo wsr3600be4p firmware UPGRADE
Affected: < 5.02
Fixed in: 5.02
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
buffalo wxr-1750dhp firmware UPGRADE
Affected: < 2.63
Fixed in: 2.63
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
buffalo wxr-1750dhp2 firmware UPGRADE
Affected: < 2.63
Fixed in: 2.63
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
buffalo wxr18000be10p firmware UPGRADE
Affected: < 5.03
Fixed in: 5.03
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
Verify at the official sourceNVD · CVE Program · Report a problem with this page Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-33280?
wcr-1166dhpl firmware: upgrade to 1.01; wsr3600be4-kh firmware: upgrade to 6.02; wsr3600be4p firmware: upgrade to 5.02. Exact commands for each OS are on this page.
Is CVE-2026-33280 being exploited?
CVE-2026-33280 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-33280 affect?
CVE-2026-33280 affects wcr-1166dhpl firmware, wsr3600be4-kh firmware, wsr3600be4p firmware. Severity is critical (CVSS 9.8). Hidden functionality issue exists in BUFFALO Wi-Fi router products, which may allow an attacker to gain access to the product’s debugging functionality, resulting in the execution of arbitrary OS commands.
How urgent is CVE-2026-33280?
Priority 47/100. Critical severity; Remotely exploitable, no login, no user action
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