vciy

CVE-2021-42020

INDEX BUILT · 2026-10-18

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A vulnerability has been identified in RUGGEDCOM i800, RUGGEDCOM i800NC, RUGGEDCOM i801, RUGGEDCOM i801NC, RUGGEDCOM i802, RUGGEDCOM i802NC…

CVE-2021-420204 of 4 sources documented this
15

rank 15 = 0 + 13 + 0 + 2 + 0

rank@v1 · backlog

Someone is already using it

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

EPSS 0.00985  ·  without this subject the record ranks 15

What it costs you if it fires

NVD CVSS base score, then the CNA's own

CVSS 5.0, from NVD  ·  without this subject the record ranks 2

It is getting worse, not staying still

FIRST EPSS series, rescorings and bad loads removed

no persisting rise in 365 days  ·  without this subject the record ranks 15

How much of the world it touches

NVD CPE configurations

1 product in the CPE ranges  ·  without this subject the record ranks 13

Someone else already set the date

CISA KEV remediation due date

no CISA due date  ·  without this subject the record ranks 15

Hindsight · the state

0.00985EPSSNOT IN KEVas of 2026-10-18
Severity7.5 HIGHreceipt
Harmunauthenticated · networkreceipt
Exploitationnone in held sources
Defenseunaffected versions publishedreceipt
Movementsteadyreceipt
PLATEAU10Minimal movement since 2022-03-09, 1602 days at 0.01, as of 2026-07-28. arc-rules@v1

Foresight · where to check next

LinuxApple macOSpolkitPalo Alto42020

This record is one instance of CWE-754, improper check for unusual or exceptional conditions. The index holds 662 prior instances of this class, 5 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.

Severity score
Siemens7.5 HIGHreceipt
NVD5 MEDIUMreceipt
Scoring standard
SiemensCVSS v3.1receipt
NVDCVSS v2.0receipt

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

Which product do you run? Check your version

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Harm, if it fires from the vector and the weakness

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Reachnetwork-reachable · no privileges required · no user interaction · low attack complexityreceipt
ImpactComplete availability lossreceipt
Scored fromCVSS v3.1 · the CNA's vectorreceipt
Weakness classCWE-754 Improper Check for Unusual or Exceptional Conditionsreceipt
Published consequencesCWE-754: Integrity, Availability: DoS: Crash, Exit, or Restart, Unexpected Statecwe-consequences@4.20

CISA KEV & Federal Remediation Deadline from the record and CISA

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

First unaffected version, by branchruggedcom ros 5.6.0receipt
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.
BOD 26-04 deadlineIf the system is reachable from the internet: 14 days. If not: fix at the next system upgrade.derived
Show full BOD 26-04 deadline

CISA has not scored it, so the directive's own defaults apply: automatable no, technical impact total. Calendar days from the KEV listing or from when you find it on a system, whichever is first. Federal agencies are bound from 7 Dec 2026, and contracts often carry it to suppliers. The directive and its table

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 CNA7.5 HIGHreceipt
CVSS, NVD5 MEDIUMreceipt
Exploit probability0.00985 · top 38% of all CVEsreceipt
Blast breadth1 product across 1 vendorderived
Assigned bysiemensreceipt
Recorded changes24 · last 18 Oct 2026derived

Affected & Fixed Versions as published

Affected productSiemens RUGGEDCOM i800; Siemens RUGGEDCOM i800NC; Siemens RUGGEDCOM i801; Siemens RUGGEDCOM i801NC; Siemens RUGGEDCOM i802; Siemens RUGGEDCOM i802NC; Siemens RUGGEDCOM i803; Siemens RUGGEDCOM i803NC…receipt
Published rangessiemens ruggedcom ros < 5.6.0receipt

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.

Unaudited dollar value2 of 3 inputs carry a receipt
Exposure$30,100over the next 30 days, if this record is yours
Movementno material movementthe record holds only daily drift and scoring model releases
Basisassumeda published average, not your estate

$30,100 = $4.99M incident cost x 0.6121449559255632 exposure x 0.00985 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.

Did this affect your environment?Answering needs an account.

Attack path

Unauthenticated network requestno credentials, no interactionSiemens RUGGEDCOM i800CWE-754 weaknessAvailability lossA:Hexploits CWE-754data compromise

What it is stated by the CNA

A vulnerability has been identified in RUGGEDCOM i800, RUGGEDCOM i800NC, RUGGEDCOM i801, RUGGEDCOM i801NC, RUGGEDCOM i802, RUGGEDCOM i802NC, RUGGEDCOM i803, RUGGEDCOM i803NC, RUGGEDCOM M2100, RUGGEDCOM M2100NC, RUGGEDCOM M2200, RUGGEDCOM M2200NC, RUGGEDCOM M969, RUGGEDCOM M969NC, RUGGEDCOM RMC30, RUGGEDCOM RMC30NC, RUGGEDCOM RMC8388 V4.X, RUGGEDCOM RMC8388 V5.X, RUGGEDCOM RMC8388NC V4.X, RUGGEDCOM RMC8388NC V5.X, RUGGEDCOM RP110, RUGGEDCOM RP110NC, RUGGEDCOM RS1600, RUGGEDCOM RS1600F, RUGGEDCOM RS1600FNC, RUGGEDCOM RS1600NC, RUGGEDCOM RS1600T, RUGGEDCOM RS1600TNC, RUGGEDCOM RS400, RUGGEDCOM RS400NC, RUGGEDCOM RS401, RUGGEDCOM RS401NC, RUGGEDCOM RS416, RUGGEDCOM RS416NC, RUGGEDCOM RS416NCv2 V receipt

Read the rest of the CNA's description

4.X, RUGGEDCOM RS416NCv2 V5.X, RUGGEDCOM RS416P, RUGGEDCOM RS416PNC, RUGGEDCOM RS416PNCv2 V4.X, RUGGEDCOM RS416PNCv2 V5.X, RUGGEDCOM RS416Pv2 V4.X, RUGGEDCOM RS416Pv2 V5.X, RUGGEDCOM RS416v2 V4.X, RUGGEDCOM RS416v2 V5.X, RUGGEDCOM RS8000, RUGGEDCOM RS8000A, RUGGEDCOM RS8000ANC, RUGGEDCOM RS8000H, RUGGEDCOM RS8000HNC, RUGGEDCOM RS8000NC, RUGGEDCOM RS8000T, RUGGEDCOM RS8000TNC, RUGGEDCOM RS900, RUGGEDCOM RS900 (32M) V4.X, RUGGEDCOM RS900 (32M) V5.X, RUGGEDCOM RS900G, RUGGEDCOM RS900G (32M) V4.X, RUGGEDCOM RS900G (32M) V5.X, RUGGEDCOM RS900GNC, RUGGEDCOM RS900GNC(32M) V4.X, RUGGEDCOM RS900GNC(32M) V5.X, RUGGEDCOM RS900GP, RUGGEDCOM RS900GPNC, RUGGEDCOM RS900L, RUGGEDCOM RS900LNC, RUGGEDCOM RS900M-GETS-C01, RUGGEDCOM RS900M-GETS-XX, RUGGEDCOM RS900M-STND-C01, RUGGEDCOM RS900M-STND-XX, RUGGEDCOM RS900MNC-GETS-C01, RUGGEDCOM RS900MNC-GETS-XX, RUGGEDCOM RS900MNC-STND-XX, RUGGEDCOM RS900MNC-STND-XX-C01, RUGGEDCOM RS900NC, RUGGEDCOM RS900NC(32M) V4.X, RUGGEDCOM RS900NC(32M) V5.X, RUGGEDCOM RS900W, RUGGEDCOM RS910, RUGGEDCOM RS910L, RUGGEDCOM RS910LNC, RUGGEDCOM RS910NC, RUGGEDCOM RS910W, RUGGEDCOM RS920L, RUGGEDCOM RS920LNC, RUGGEDCOM RS920W, RUGGEDCOM RS930L, RUGGEDCOM RS930LNC, RUGGEDCOM RS930W, RUGGEDCOM RS940G, RUGGEDCOM RS940GNC, RUGGEDCOM RS969, RUGGEDCOM RS969NC, RUGGEDCOM RSG2100, RUGGEDCOM RSG2100 (32M) V4.X, RUGGEDCOM RSG2100 (32M) V5.X, RUGGEDCOM RSG2100NC, RUGGEDCOM RSG2100NC(32M) V4.X, RUGGEDCOM RSG2100NC(32M) V5.X, RUGGEDCOM RSG2100P, RUGGEDCOM RSG2100P (32M) V4.X, RUGGEDCOM RSG2100P (32M) V5.X, RUGGEDCOM RSG2100PNC, RUGGEDCOM RSG2100PNC (32M) V4.X, RUGGEDCOM RSG2100PNC (32M) V5.X, RUGGEDCOM RSG2200, RUGGEDCOM RSG2200NC, RUGGEDCOM RSG2288 V4.X, RUGGEDCOM RSG2288 V5.X, RUGGEDCOM RSG2288NC V4.X, RUGGEDCOM RSG2288NC V5.X, RUGGEDCOM RSG2300 V4.X, RUGGEDCOM RSG2300 V5.X, RUGGEDCOM RSG2300NC V4.X, RUGGEDCOM RSG2300NC V5.X, RUGGEDCOM RSG2300P V4.X, RUGGEDCOM RSG2300P V5.X, RUGGEDCOM RSG2300PNC V4.X, RUGGEDCOM RSG2300PNC V5.X, RUGGEDCOM RSG2488 V4.X, RUGGEDCOM RSG2488 V5.X, RUGGEDCOM RSG2488NC V4.X, RUGGEDCOM RSG2488NC V5.X, RUGGEDCOM RSG907R, RUGGEDCOM RSG908C, RUGGEDCOM RSG909R, RUGGEDCOM RSG910C, RUGGEDCOM RSG920P V4.X, RUGGEDCOM RSG920P V5.X, RUGGEDCOM RSG920PNC V4.X, RUGGEDCOM RSG920PNC V5.X, RUGGEDCOM RSL910, RUGGEDCOM RSL910NC, RUGGEDCOM RST2228, RUGGEDCOM RST2228P, RUGGEDCOM RST916C, RUGGEDCOM RST916P. The third-party component, in its TFTP functionality fails to check for null terminations in file names. If an attacker were to exploit this, it could result in data corruption, and possibly a hard-fault of the application.

NVD's analysis a second authority

severity
5 AV:N/AC:L/Au:N/C:N/I:N/A:P
weakness
CWE-754
affected versions
siemens ruggedcom ros < 5.6.0
also scored by
productcert@siemens.com 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H · nvd@nist.gov 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

The CNA scored it 7.5 and NVD 5. Both are shown because both were published; we do not pick one.

check it yourself cert-portal.siemens.com cert-portal.siemens.com receipt

Movement the material steps

9 Mar 20220.00885
7 Mar 20235.5e-4 · scoring model v2023.03.01
17 Mar 20250.00128 · scoring model v2025.03.14
15 Jun 20260.00946 · scoring model v2026.06.15
28 Jul 20260.00985
Show all 24 observations
9 Mar 20220.00885
7 Mar 20235.5e-4
8 Mar 20230.00055
15 Mar 20230.00078
19 Aug 20230.00086
29 Sep 20230.00089
12 Oct 20240.00091
21 Nov 20240.00103
17 Dec 20240.00044
17 Mar 20250.00128
19 Mar 20250.00163
25 Mar 20250.00216
26 Mar 20250.00251
29 Mar 20250.00247
30 Mar 20250.00251
6 Apr 20250.00375
18 Apr 20250.0054
20 Apr 20250.00536
9 May 20250.00457
12 Aug 20250.00468
12 Apr 20260.00339
15 Jun 20260.00946
7 Jul 20260.0097
28 Jul 20260.00985

24 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 0.00985Published2022-03-08Index as of2026-07-28

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

Published 2022-03-08 receipt · Index as of 2026-07-28 derived

The pattern, elsewhere

This record is one instance of CWE-754, improper check for unusual or exceptional conditions. The index holds 662 prior instances of this class, 5 KEV-listed. The nearest of its KEV-listed records are drawn beside this. cwe-consequences@4.20

CVE-2025-39682 · Linuxmatches 6 of 9KEV listed · 2025receipt
CVE-2023-41993 · Apple macOSmatches 5 of 9KEV listed · 2023receipt
CVE-2023-41992 · Apple macOSmatches 4 of 9KEV listed · 2023receipt
CVE-2021-3560 · polkitmatches 4 of 9KEV listed · 2022receipt
CVE-2024-3393 · Palo Alto Networks Cloud NGFWonly 1 attribute comparableKEV listed · 2024receipt

"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

662 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

Fixed with these, by one advisory

Listed because one advisory covers them, not because they are the same defect. Each record's own state is on its own page.

Grouping: held values

Browse the index from here

These are index-wide views, not findings about CVE-2021-42020.

What usually comes next

Everything above needs no account. What is below is work: assembling it, scoping it to your estate, watching it, and handing it to someone else.

Everything on this page is free. Public data. Withholding it protects nothing.