CVE-2021-44693
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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…
rank 27 = 0 + 12 + 0 + 15 + 0
rank@v1 · scheduled
Someone is already using it
CISA KEV catalog · public proof-of-concept · FIRST EPSS
EPSS 0.00766 · without this subject the record ranks 27
What it costs you if it fires
NVD CVSS base score, then the CNA's own
CVSS 4.9, 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 27
How much of the world it touches
NVD CPE configurations
88 products in the CPE ranges · without this subject the record ranks 12
Someone else already set the date
CISA KEV remediation due date
no CISA due date · without this subject the record ranks 27
Hindsight · the state
Foresight · where to check next
This record is one instance of CWE-1284, improper validation of specified quantity in input. The index holds 456 prior instances of this class, 2 KEV-listed. The nearest of its KEV-listed records are drawn beside this. taxonomy@v1
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Harm, if it fires from the vector and the weakness
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CISA KEV & Federal Remediation Deadline from the record and CISA
The fix, and how long it's been waiting.
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
Affected & Fixed Versions as published
Show all 88 published ranges
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.
$23,400 = $4.99M incident cost x 0.6121449559255632 exposure x 0.00766 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.
Attack path
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-1284
- 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 4.9 CVSS:3.1/AV:N/AC:L/PR:H/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
check it yourself cert-portal.siemens.com receipt
Movement the material steps
This score more than doubled inside 72 hours. Both observations are in the full history below.
Show all 28 observations
28 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
Exploit probability more than doubled between 2025-12-14 and 2025-12-16 (0.00112 → 0.00262) and the record had been public for 3 years, 10 months when this index was last written.
The pattern, elsewhere
This record is one instance of CWE-1284, improper validation of specified quantity in input. The index holds 456 prior instances of this class, 2 KEV-listed. The nearest of its KEV-listed records are drawn beside this. cwe-consequences@4.20
"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
456 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
No record cites this identifier and it carries no alias. The advisory that covers it is below.
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
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What usually comes next
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