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Gc108p FirmwareOperating system · Netgear

CVE-2021-40866

HIGH · 8.8 CVSS v3.1 Published 2021-09-13
Fix available
A fix is available. Upgrade to 1.0.3.2 / 1.0.5.3 or later.
See remediation →
93/100
Remediation priority · Urgent
Public exploit No privileges 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
Certain NETGEAR smart switches are affected by a remote admin password change by an unauthenticated attacker via the (disabled by default) /sqfs/bin/sccd daemon, which fails to check authentication when the authentication TLV is missing from a received NSDP packet. This affects GC108P before 1.0.8.2, GC108PP before 1.0.8.2, GS108Tv3 before 7.0.7.2, GS110TPP before 7.0.7.2, GS110TPv3 before 7.0.7.2, GS110TUP before 1.0.5.3, GS308T before 1.0.3.2, GS310TP before 1.0.3.2, GS710TUP before 1.0.5.3, GS716TP before 1.0.4.2, GS716TPP before 1.0.4.2, GS724TPP before 2.0.6.3, GS724TPv2 before 2.0.6.3, GS728TPPv2 before 6.0.8.2, GS728TPv2 before 6.0.8.2, GS750E before 1.0.1.10, GS752TPP before 6.0.8.2, GS752TPv2 before 6.0.8.2, MS510TXM before 1.0.4.2, and MS510TXUP before 1.0.4.2.

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

A detailed technical summary for this CVE is being prepared.

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
Gc108p FirmwareOperating system
Affected:< 1.0.8.2
Gc108pp FirmwareOperating system
Affected:< 1.0.8.2
Gs108t FirmwareOperating system
Affected:< 7.0.7.2
Gs110tpp FirmwareOperating system
Affected:< 7.0.7.2
Gs110tp FirmwareOperating system
Affected:< 7.0.7.2
Gs110tup FirmwareOperating system
Affected:< 1.0.5.3
Gs308t FirmwareOperating system
Affected:< 1.0.3.2
Gs310tp FirmwareOperating system
Affected:< 1.0.3.2

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 1.0.3.2 / 1.0.5.3 / 1.0.8.2 or later
Fixed in 1.0.3.21.0.5.31.0.8.2
Recommended fix High confidence

Upgrade to firmware version 1.0.8.2 (GC108P/GC108PP), 7.0.7.2 (GS108Tv3/GS110TPP/GS110TPv3), 1.0.5.3 (GS110TUP), or 1.0.3.2 (GS308T/GS310TP) as appropriate for your model

  1. Identify the exact model number of the affected NETGEAR switch from the list: GC108P, GC108PP, GS108Tv3, GS110TPP, GS110TPv3, GS110TUP, GS308T, or GS310TP
  2. Locate the firmware download page for your specific model on the official NETGEAR support site (kb.netgear.com)
  3. Download the latest firmware version that meets or exceeds the fixed version for your model: GC108P/GC108PP requires 1.0.8.2 or higher; GS108Tv3/GS110TPP/GS110TPv3 requires 7.0.7.2 or higher; GS110TUP requires 1.0.5.3 or higher; GS308T/GS310TP requires 1.0.3.2 or higher
  4. Access the switch web management interface or use NETGEAR's NMS software
  5. Navigate to the Firmware Update section (typically under Maintenance or Administration)
  6. Upload and apply the downloaded firmware file
  7. Allow the switch to reboot and complete the firmware installation
  8. After reboot, verify the firmware version has been updated successfully
Caveat Firmware upgrades may reset some configuration settings; backup current configuration before upgrading

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

We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $1,950. Get the upgrade done

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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

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