vciy

CVE-2020-27866

INDEX BUILT · 2026-09-20

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This vulnerability allows network-adjacent attackers to bypass authentication on affected installations of NETGEAR R6020, R6080, R6120, R6220, R6260…

CVE-2020-278664 of 4 sources documented this
35

rank 35 = 2 + 22 + 1 + 10 + 0

rank@v1 · scheduled

Someone is already using it

CISA KEV catalog · public proof-of-concept · FIRST EPSS

EPSS 0.08656  ·  without this subject the record ranks 33

What it costs you if it fires

NVD CVSS base score, then the CNA's own

CVSS 8.8, from NVD  ·  without this subject the record ranks 13

It is getting worse, not staying still

FIRST EPSS series, rescorings and bad loads removed

rose on 2025-07-05  ·  without this subject the record ranks 34

How much of the world it touches

NVD CPE configurations

19 products in the CPE ranges  ·  without this subject the record ranks 25

Someone else already set the date

CISA KEV remediation due date

no CISA due date  ·  without this subject the record ranks 35

Unaudited dollar value2 of 3 inputs carry a receipt
Exposure$432,000over the next 30 days, if this record is yours
Movement+$30,200on 2026-02-04, the last material move, 4 months before this reading
Basisassumeda published average, not your estate

$432,000 = $4.99M incident cost x 1 exposure x 0.08656 likelihood

udv@v1 · unaudited · wrong for you until you say what you run

$4.99M is the cost of a breach that happened, from IBM Cost of a Data Breach Report 2026, global average. It is not the value of any asset of yours. That average already covers breaches of every severity, so scaling it by exposure understates a partial-impact record. That is an assumption, not a measurement. Your own asset value goes in the decision record.

Hindsight · the state

0.08656EPSSNOT IN KEVas of 2026-09-20
Severity8.8 HIGHreceipt
Harmtotal lossreceipt
Exploitationnone in held sources
Defenseunaffected versions publishedreceipt
Movementthreshold crossedreceipt
RISING10Risen from 0.01095 to 0.08656 across 44 observations. arc-rules@v1

Foresight · where to check next

Fortinet FortiOSJetBrainsF5 BIG-IPFortinet FortiWebKentico Xperience27866

This record is one instance of CWE-288, authentication bypass using an alternate path or channel. The index holds 681 prior instances of this class, 20 KEV-listed. The nearest of its KEV-listed records are drawn beside this. taxonomy@v1

Full pattern panel

Prior records in this weakness class. Each is its own record, dated and receipted.
Color is a claim, not decoration:the hostile worldthe defenseno signalspoke length is how much of the record matches, not how bad it is

Sources disagree here.

Scoring standard
ZdiCVSS v3.0receipt
NVDCVSS v3.1receipt

Both shown, dated. We don't pick winners. disagreement-rules@v1

Running NETGEAR Multiple Routers? Check your version

A deterministic range check against the ranges this record publishes. It tells you where a version sits in the record, not whether your deployment is exploitable. No account needed.

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Harm, if it fires from the vector and the weakness

Written for the ticket you're about to file.

Reachreachable from an adjacent network · no privileges required · no user interaction · low attack complexityreceipt
ImpactComplete confidentiality, integrity and availability lossreceipt
Scored fromCVSS v3.0 · the CNA's vectorreceipt
Weakness classCWE-288 Authentication Bypass Using an Alternate Path or Channelreceipt
Published consequencesCWE-288: Access Control: Bypass Protection Mechanism[email protected]

CISA KEV & Federal Remediation Deadline from the record and CISA

The fix, and how long it's been waiting.

First unaffected version, by branchac2100 firmware 1.2.0.76; ac2400 firmware 1.2.0.76; ac2600 firmware 1.2.0.76; r6020 firmware 1.0.0.48; r6080 firmware 1.0.0.48; r6120 firmware 1.0.0.76receipt
Patch available sinceNo dated patch-availability record in held sources. The index holds reference URLs without dates and only the current revision of the CVE record, so the day a fix first existed cannot be derived. Only the versions it landed in.

Exploit Status & Known PoCs a ladder, not a score

Current rung: Nothing observed in held sources.

  • RUNG 1Nothing observed in held sources
  • RUNG 2Proof-of-concept published
  • RUNG 3Exploited in the wild · CISA KEV listed
  • RUNG 4Ransomware campaign use known

Authority who says so

CVSS, the CNA8.8 HIGHreceipt
CVSS, NVD8.8 HIGHreceipt
Exploit probability0.08656 · top 5% of all CVEsreceipt
Blast breadth19 products across 1 vendorderived
Assigned byzdireceipt
Recorded changes44 · last 19 Sep 2026derived

Affected & Fixed Versions as published

Affected productNETGEAR Multiple Routersreceipt
Published rangesnetgear ac2100 firmware < 1.2.0.76; netgear ac2400 firmware < 1.2.0.76; netgear ac2600 firmware < 1.2.0.76; netgear r6700 firmware < 1.2.0.76receipt
Show all 19 published ranges
netgear ac2100 firmware < 1.2.0.76
netgear ac2400 firmware < 1.2.0.76
netgear ac2600 firmware < 1.2.0.76
netgear r6700 firmware < 1.2.0.76
netgear r6800 firmware < 1.2.0.76
netgear r6900 firmware < 1.2.0.76
netgear r7200 firmware < 1.2.0.76
netgear r7350 firmware < 1.2.0.76
netgear r7400 firmware < 1.2.0.76
netgear r7450 firmware < 1.2.0.76
netgear r6220 firmware < 1.1.0.104
netgear r6230 firmware < 1.1.0.104
netgear r6260 firmware < 1.1.0.78
netgear r6330 firmware < 1.1.0.78
netgear r6350 firmware < 1.1.0.78
netgear r6850 firmware < 1.1.0.78
netgear r6120 firmware < 1.0.0.76
netgear r6020 firmware < 1.0.0.48
netgear r6080 firmware < 1.0.0.48

A rung lights from a row in the index, never from an assessment. "Held sources" is the true scope of the claim: this index reads the CVE record, NVD, CISA KEV, FIRST's EPSS and public proof-of-concept repositories, and it does not observe attacks.

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Attack path

Adjacent networkno credentials, no interactionNETGEAR Multiple RoutersCWE-288 weaknessFull compromise (C/I/A)C:H / I:H / A:Hexploits CWE-288data compromise

What it is stated by the CNA

This vulnerability allows network-adjacent attackers to bypass authentication on affected installations of NETGEAR R6020, R6080, R6120, R6220, R6260, R6700v2, R6800, R6900v2, R7450, JNR3210, WNR2020, Nighthawk AC2100, and Nighthawk AC2400 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the mini_httpd service, which listens on TCP port 80 by default. The issue results from incorrect string matching logic when accessing protected pages. An attacker can leverage this in conjunction with other vulnerabilities to execute code in the context of root. Was ZDI-CAN-11355. receipt

NVD's analysis a second authority

severity
8.8 CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
weakness
CWE-288; CWE-287
affected versions
netgear ac2100 firmware < 1.2.0.76; netgear ac2400 firmware < 1.2.0.76; netgear ac2600 firmware < 1.2.0.76; and 16 more, listed in full below

check it yourself kb.netgear.com zerodayinitiative.com receipt

Dated events

2022-04-01EPSS moved 0.07 to 0.012026-06-15EPSS moved 0.90 to 0.09

Movement the material steps

14 Apr 20210.01095
7 Mar 20230.00339 · scoring model v2023.03.01
17 Mar 20250.72759 · crossed 0.10 and 0.50 · scoring model v2025.03.14
18 Mar 20250.61811
23 Mar 20250.72759
24 Mar 20250.61811
26 Mar 20250.72759
28 Mar 20250.87209
28 Oct 20250.9036 · crossed 0.90
1 Nov 20250.89755 · crossed 0.90
4 Nov 20250.9036 · crossed 0.90
18 Nov 20250.6082 · crossed 0.90
21 Nov 20250.9036 · crossed 0.90
1 Dec 20250.89755 · crossed 0.90
4 Dec 20250.9036 · crossed 0.90
1 Jan 20260.89755 · crossed 0.90
4 Jan 20260.9036 · crossed 0.90
1 Feb 20260.89755 · crossed 0.90
4 Feb 20260.9036 · crossed 0.90
15 Jun 20260.08656 · crossed 0.10 and 0.50 and 0.90 · scoring model v2026.06.15
Show all 44 observations
14 Apr 20210.01095
6 Jan 20220.04733
4 Feb 20220.07469
1 Apr 20220.01005
7 Mar 20230.00339
10 Mar 20230.00365
18 Sep 20230.00517
2 Oct 20230.00433
23 Nov 20230.00363
15 May 20240.00450
17 Jul 20240.00505
21 Aug 20240.00494
29 Oct 20240.00415
17 Dec 20240.00561
4 Feb 20250.00795
17 Mar 20250.72759
18 Mar 20250.61811
23 Mar 20250.72759
24 Mar 20250.61811
26 Mar 20250.72759
28 Mar 20250.87209
29 Mar 20250.89672
30 Mar 20250.87209
2 Apr 20250.85467
5 Jul 20250.89755
24 Sep 20250.89757
7 Oct 20250.89755
28 Oct 20250.9036
1 Nov 20250.89755
4 Nov 20250.9036
18 Nov 20250.6082
21 Nov 20250.9036
1 Dec 20250.89755
4 Dec 20250.9036
1 Jan 20260.89755
4 Jan 20260.9036
1 Feb 20260.89755
4 Feb 20260.9036
12 Feb 20260.90841
1 Mar 20260.90258
4 Mar 20260.90841
17 Mar 20260.90779
10 May 20260.9036
15 Jun 20260.08656

44 observations held. A highlighted step crossed a promotion threshold. A step marked with a scoring model moved because the instrument was replaced, not because the vulnerability changed. receipt

The full biography

EPSS 0.08656Published2021-02-11Index as of2026-06-15

The record had been public for 5 years, 4 months when this index was last written.

Published 2021-02-11 receipt · Index as of 2026-06-15 derived

The pattern, elsewhere

This record is one instance of CWE-288, authentication bypass using an alternate path or channel. The index holds 681 prior instances of this class, 20 KEV-listed. The nearest of its KEV-listed records are drawn beside this. [email protected]

CVE-2024-55591 · Fortinet FortiOSmatches 7 of 10KEV listed · 2025receipt
CVE-2024-27198 · JetBrains TeamCitymatches 7 of 10KEV listed · 2024receipt
CVE-2023-42793 · JetBrains TeamCitymatches 7 of 10KEV listed · 2023receipt
CVE-2023-46747 · F5 BIG-IPmatches 7 of 10KEV listed · 2023receipt
CVE-2026-24858 · Fortinet FortiWebmatches 7 of 10KEV listed · 2026receipt
CVE-2025-2746 · Kentico Xperiencematches 7 of 10KEV listed · 2025receipt

"Matches n of m" counts the attributes the two records can both be compared on: the CVSS metrics they share a version of, any weakness class beyond this one, and the vendor. fit-rules@v1

681 records in this class held. The six above are drawn from the ones CISA has listed as exploited, ranked by how much of the record matches this one. That is why every one of them is KEV-listed: the pool is, so the colour on those spokes says nothing the pool has not already said.

No curated product neighbourhood is held for this product, so the records above are the nearest this index can name. The neighbourhood table covers a small set of products and is extended by hand.

Siblings and hubs

Records related to this one

Its defect family

netgear multiple routers

Grouped by shared product and weakness, not by shared vulnerability. Each record's own state is on its own page.

Family membership: held values

Nothing we hold separates this record from the others in its defect family. This page is kept and dated, and the defect family's own page is the one we offer for indexing: the whole group.

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What usually comes next

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