Certain NETGEAR smart switches are affected by a remote admin password change by an unauthenticated attacker via the (disabled by default)…

published 2021-09-13 5y ago modified 2026-06-17 4mo ago also EUVD-2021-28021

cvss: 9.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.8%; EPSS 1.8% chance of exploitation in 30 days, percentile 78%
public exploits: 0; none known

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.

Patch / fix

fixed in 20

netgear gc108p_firmware 1.0.8.2
netgear gc108pp_firmware 1.0.8.2
netgear gs108t_firmware 7.0.7.2
netgear gs110tpp_firmware 7.0.7.2
netgear gs110tp_firmware 7.0.7.2
netgear gs110tup_firmware 1.0.5.3
netgear gs308t_firmware 1.0.3.2
netgear gs310tp_firmware 1.0.3.2
netgear gs710tup_firmware 1.0.5.3
netgear gs716tp_firmware 1.0.4.2
netgear gs716tpp_firmware 1.0.4.2
netgear gs724tpp_firmware 2.0.6.3
netgear gs724tp_firmware 2.0.6.3
netgear gs728tpp_firmware 6.0.8.2
netgear gs728tp_firmware 6.0.8.2
netgear gs750e_firmware 1.0.1.10
netgear gs752tpp_firmware 6.0.8.2
netgear gs752tp_firmware 6.0.8.2
netgear ms510txm_firmware 1.0.4.2
netgear ms510txup_firmware 1.0.4.2

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Exploit prediction

1.76% chance of exploitation in the next 30 days, higher than 78% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

gynvael.coldwind.pl https://gynvael.coldwind.pl/?id=740 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	3.1	9.8	CVSS:3.1/AC:L/AV:N/A:H/C:H/I:H/PR:N/S:U/UI:N
CNA	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	3.1	8.8	CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	5.4	AV:A/AC:M/Au:N/C:P/I:P/A:P

References

gynvael.coldwind.pl /?id=740
exploit, third-party-advisory
kb.netgear.com /000063978/Security-Advisory-for-Multiple-Vulnerabilities-on-Some-Smart-Switches-PSV-2021-0140-PSV-2021-0144-P
vendor-advisory

Sources

CVE List CVE-2021-40866
NVD CVE-2021-40866

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