vciy

CVE-2021-44694

INDEX BUILT · 2026-10-18

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Affected devices don't process correctly certain special crafted packets sent to port 102/tcp, which could allow an attacker to cause a denial of…

CVE-2021-446944 of 4 sources documented this
29

rank 29 = 0 + 14 + 0 + 15 + 0

rank@v1 · scheduled

Someone is already using it

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

EPSS 0.00658  ·  without this subject the record ranks 29

What it costs you if it fires

NVD CVSS base score, then the CNA's own

CVSS 5.5, from the CNA  ·  without this subject the record ranks 15

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 29

How much of the world it touches

NVD CPE configurations

88 products in the CPE ranges  ·  without this subject the record ranks 14

Someone else already set the date

CISA KEV remediation due date

no CISA due date  ·  without this subject the record ranks 29

Hindsight · the state

0.00658EPSSNOT IN KEVas of 2026-10-18
Severity5.5 MEDIUMreceipt
Harmpartial impactreceipt
Exploitationnone in held sources
Defenseunaffected versions publishedreceipt
Movementdoubled within 72hreceipt
PLATEAU10Minimal movement since 2022-12-14, 1399 days at 0.01, as of 2026-10-13. arc-rules@v1

Foresight · where to check next

No weakness class or product neighbourhood is held for this record, so this index cannot name anywhere to check next. That is an absence in the record, not a finding about the software.

Color is a claim, not decoration:the hostile worldthe defenseno signal

Which product do you run? 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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Matches your own product list against every record this index holds, and tells you when one of them moves.

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Patch by…

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Harm, if it fires from the vector and the weakness

Written for the ticket you're about to file.

Reachnetwork-reachable · high privileges required · no user interaction · low attack complexityreceipt
ImpactPartial integrity loss; complete availability lossreceipt
Scored fromCVSS v3.1 · the CNA's vectorreceipt
Weakness classCWE-1287 Improper Validation of Specified Type of Inputreceipt
Published consequencesCWE-1287: Other: Varies by Contextcwe-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 branchsimatic s7-1200 cpu 4.6.0; simatic s7-1200 cpu 1211c firmware 4.6.0; simatic s7-1200 cpu 1212c firmware 4.6.0; simatic s7-1200 cpu 1212fc firmware 4.6.0; simatic s7-1200 cpu 1214c firmware 4.6.0…receipt
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 CNA5.5 MEDIUMreceipt
Exploit probability0.00658 · top 50% of all CVEsreceipt
Blast breadth79 products across 1 vendorderived
Assigned bysiemensreceipt
Recorded changes29 · last 18 Oct 2026derived

Affected & Fixed Versions as published

Affected productSiemens SIMATIC Drive Controller CPU 1504D TF; Siemens SIMATIC Drive Controller CPU 1507D TF; Siemens SIMATIC ET 200SP Open Controller CPU 1515SP PC2 (incl. SIPLUS variants)…receipt
Published rangessiemens simatic s7-plcsim advanced firmware < 5.0; siemens simatic s7-1200 cpu 1211c firmware < 4.6.0; siemens simatic s7-1200 cpu 1212c firmware < 4.6.0; siemens simatic s7-1200 cpu 1212fc firmware < 4.6.0receipt
Show all 88 published ranges
siemens simatic s7-plcsim advanced firmware < 5.0
siemens simatic s7-1200 cpu 1211c firmware < 4.6.0
siemens simatic s7-1200 cpu 1212c firmware < 4.6.0
siemens simatic s7-1200 cpu 1212fc firmware < 4.6.0
siemens simatic s7-1200 cpu 1214 fc firmware < 4.6.0
siemens simatic s7-1200 cpu 1214c firmware < 4.6.0
siemens simatic s7-1200 cpu 1214fc firmware < 4.6.0
siemens simatic s7-1200 cpu 1215 fc firmware < 4.6.0
siemens simatic s7-1200 cpu 1215c firmware < 4.6.0
siemens simatic s7-1200 cpu 1215fc firmware < 4.6.0
siemens simatic s7-1200 cpu 1217c firmware < 4.6.0
siemens simatic s7-1200 cpu 12 1211c firmware < 4.6.0
siemens simatic s7-1200 cpu 12 1212c firmware < 4.6.0
siemens simatic s7-1200 cpu 12 1212fc firmware < 4.6.0
siemens simatic s7-1200 cpu 12 1214c firmware < 4.6.0
siemens simatic s7-1200 cpu 12 1214fc firmware < 4.6.0
siemens simatic s7-1200 cpu 12 1215c firmware < 4.6.0
siemens simatic s7-1200 cpu 12 1215fc firmware < 4.6.0
siemens simatic s7-1200 cpu 12 1217c firmware < 4.6.0
siemens siplus s7-1200 cp 1243-1 rail firmware < 4.6.0
siemens siplus s7-1200 cp 1243-1 firmware < 4.6.0
siemens simatic s7-1500 cpu 1507s firmware < 3.0.1
siemens simatic s7-1500 cpu 1507s f firmware < 3.0.1
siemens simatic s7-1500 cpu 1508s firmware < 3.0.1
siemens simatic s7-1500 cpu 1508s f firmware < 3.0.1
siemens simatic s7-1500 cpu 1510sp firmware < 3.0.1
siemens simatic s7-1500 cpu 1510sp-1 firmware < 3.0.1
siemens simatic s7-1500 cpu 1511-1 firmware < 3.0.1
siemens simatic s7-1500 cpu 1511-1 pn firmware < 3.0.1
siemens simatic s7-1500 cpu 1511c firmware < 3.0.1
siemens simatic s7-1500 cpu 1511c-1 firmware < 3.0.1
siemens simatic s7-1500 cpu 1511f-1 firmware < 3.0.1
siemens simatic s7-1500 cpu 1511f-1 pn firmware < 3.0.1
siemens simatic s7-1500 cpu 1511t-1 firmware < 3.0.1
siemens simatic s7-1500 cpu 1511tf-1 firmware < 3.0.1
siemens simatic s7-1500 cpu 1512c firmware < 3.0.1
siemens simatic s7-1500 cpu 1512c-1 firmware < 3.0.1
siemens simatic s7-1500 cpu 1512sp-1 firmware < 3.0.1
siemens simatic s7-1500 cpu 1512spf-1 firmware < 3.0.1
siemens simatic s7-1500 cpu 1513-1 firmware < 3.0.1
siemens simatic s7-1500 cpu 1513-1 pn firmware < 3.0.1
siemens simatic s7-1500 cpu 1513f-1 firmware < 3.0.1
siemens simatic s7-1500 cpu 1513f-1 pn firmware < 3.0.1
siemens simatic s7-1500 cpu 1513r-1 firmware < 3.0.1
siemens simatic s7-1500 cpu 1515-2 firmware < 3.0.1
siemens simatic s7-1500 cpu 1515-2 pn firmware < 3.0.1
siemens simatic s7-1500 cpu 151511c-1 firmware < 3.0.1
siemens simatic s7-1500 cpu 151511f-1 firmware < 3.0.1
siemens simatic s7-1500 cpu 1515f-2 firmware < 3.0.1
siemens simatic s7-1500 cpu 1515f-2 pn firmware < 3.0.1
siemens simatic s7-1500 cpu 1515r-2 firmware < 3.0.1
siemens simatic s7-1500 cpu 1515t-2 firmware < 3.0.1
siemens simatic s7-1500 cpu 1515tf-2 firmware < 3.0.1
siemens simatic s7-1500 cpu 1516-3 firmware < 3.0.1
siemens simatic s7-1500 cpu 1516-3 dp firmware < 3.0.1
siemens simatic s7-1500 cpu 1516-3 pn firmware < 3.0.1
siemens simatic s7-1500 cpu 1516-3 pn\/dp firmware < 3.0.1
siemens simatic s7-1500 cpu 1516f-3 firmware < 3.0.1
siemens simatic s7-1500 cpu 1516f-3 pn\/dp firmware < 3.0.1
siemens simatic s7-1500 cpu 1516pro-2 firmware < 3.0.1
siemens simatic s7-1500 cpu 1516pro f firmware < 3.0.1
siemens simatic s7-1500 cpu 1516t-3 firmware < 3.0.1
siemens simatic s7-1500 cpu 1516tf-3 firmware < 3.0.1
siemens simatic s7-1500 cpu 1517-3 firmware < 3.0.1
siemens simatic s7-1500 cpu 1517-3 dp firmware < 3.0.1
siemens simatic s7-1500 cpu 1517-3 pn firmware < 3.0.1
siemens simatic s7-1500 cpu 1517-3 pn\/dp firmware < 3.0.1
siemens simatic s7-1500 cpu 1517f-3 firmware < 3.0.1
siemens simatic s7-1500 cpu 1517f-3 pn\/dp firmware < 3.0.1
siemens simatic s7-1500 cpu 1517tf-3 firmware < 3.0.1
siemens simatic s7-1500 cpu 1518 firmware < 3.0.1
siemens simatic s7-1500 cpu 1518-4 firmware < 3.0.1
siemens simatic s7-1500 cpu 1518-4 dp firmware < 3.0.1
siemens simatic s7-1500 cpu 1518-4 pn firmware < 3.0.1
siemens simatic s7-1500 cpu 1518-4 pn\/dp firmware < 3.0.1
siemens simatic s7-1500 cpu 1518-4 pn\/dp mfp firmware < 3.0.1
siemens simatic s7-1500 cpu 1518f-4 firmware < 3.0.1
siemens simatic s7-1500 cpu 1518f-4 pn\/dp firmware < 3.0.1
siemens simatic s7-1500 cpu 1518hf-4 firmware < 3.0.1
siemens simatic s7-1500 cpu 1518t-4 firmware < 3.0.1
siemens simatic s7-1500 cpu 1518tf-4 firmware < 3.0.1
siemens simatic s7-1500 cpu 15pro-2 firmware < 3.0.1
siemens simatic s7-1500 cpu 15prof-2 firmware < 3.0.1
siemens simatic s7-1500 cpu cpu 1513pro-2 firmware < 3.0.1
siemens simatic s7-1500 cpu cpu 1513prof-2 firmware < 3.0.1
siemens siplus et 200sp cp 1542sp-1 irc tx rail firmware < 3.0.1
siemens siplus et 200sp cp 1543sp-1 isec firmware < 3.0.1
siemens siplus et 200sp cp 1543sp-1 isec tx rail firmware < 3.0.1

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$23,600over 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

$23,600 = $4.99M incident cost x 0.7179585840212677 exposure x 0.00658 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

Network requestrequires high privilegesSiemens TIM 1531 IRCCWE-1287 weaknessAvailability lossA:Hexploits CWE-1287data compromise

What it is stated by the CNA

Affected devices don't process correctly certain special crafted packets sent to port 102/tcp, which could allow an attacker to cause a denial of service in the device. receipt

NVD's analysis a second authority

weakness
CWE-1287; CWE-20
affected versions
siemens simatic s7-plcsim advanced firmware < 5.0; siemens simatic s7-1200 cpu 1211c firmware < 4.6.0; siemens simatic s7-1200 cpu 1212c firmware < 4.6.0; and 85 more, listed in full below
also scored by
productcert@siemens.com 5.5 CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/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

check it yourself cert-portal.siemens.com receipt

Movement the material steps

14 Dec 20220.00885
7 Mar 20234.6e-4 · scoring model v2023.03.01
17 Mar 20250.00063 · scoring model v2025.03.14
15 Jun 20260.00617 · scoring model v2026.06.15
13 Oct 20260.00658

This score more than doubled inside 72 hours. Both observations are in the full history below.

Show all 29 observations
14 Dec 20220.00885
7 Mar 20234.6e-4
8 Mar 20230.00046
12 Apr 20230.00044
12 Jul 20230.00046
13 Sep 20230.00044
13 Nov 20230.00053
20 Dec 20230.00073
5 Jul 20240.00107
17 Dec 20240.00044
17 Mar 20250.00063
19 Mar 20250.00065
29 Mar 20250.00062
30 Mar 20250.00065
23 Jun 20250.00071
7 Sep 20250.00089
9 Oct 20250.00095
17 Oct 20250.00098
29 Oct 20250.00095
18 Nov 20250.00193
21 Nov 20250.00095
16 Dec 20250.00112
17 Dec 20250.00247
26 Dec 20250.00262
6 Jan 20260.00224
14 Feb 20260.00193
15 Jun 20260.00617
28 Sep 20260.00634
13 Oct 20260.00658

29 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 0.00658Published2022-12-13Index as of2026-10-13

Exploit probability more than doubled between 2025-12-16 and 2025-12-17 (0.00112 → 0.00247) and the record had been public for 3 years, 10 months when this index was last written.

Published 2022-12-13 receipt · Index as of 2026-10-13 derived

Siblings and hubs

Records related to this one

Fixed with these, by one advisory

Of the 4 records in this advisory that state one, this holds the lowest EPSS percentile: 0.47237.

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

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What usually comes next

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