CVE-2021-40866: 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

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

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.

Description from the National Vulnerability Database, published by MITRE

What it means for a small business

Gc108p Firmware is network equipment or remote-access software: the box between your office and the internet. These are a favorite target because breaking one opens the whole office.

If an IT provider set it up, ask them to confirm the firmware version and the date it was updated. If nobody looks after it, that's the bigger problem.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 1.8%, higher than 77% of CVEs. That’s above average: worth scheduling this week. Scored October 28, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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