vciy

CVE-2021-44521

INDEX BUILT · 2026-09-20

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Remote code execution for scripted UDFs

CVE-2021-445214 of 4 sources documented this
51

rank 51 = 23 + 23 + 0 + 5 + 0

rank@v1 · this cycle

Someone is already using it

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

EPSS 0.55006  ·  without this subject the record ranks 28

What it costs you if it fires

NVD CVSS base score, then the CNA's own

CVSS 9.1, from NVD  ·  without this subject the record ranks 28

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 51

How much of the world it touches

NVD CPE configurations

3 products in the CPE ranges  ·  without this subject the record ranks 46

Someone else already set the date

CISA KEV remediation due date

no CISA due date  ·  without this subject the record ranks 51

Unaudited dollar value2 of 3 inputs carry a receipt
Exposure$2.74Mover the next 30 days, if this record is yours
Movement+$1.39Mon 2025-11-21, the last material move, 8 months before this reading
Basisassumeda published average, not your estate

$2.74M = $4.99M incident cost x 1 exposure x 0.55006 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

0.55006EPSSNOT IN KEVas of 2026-09-20
Severity9.1 CRITICALreceipt
Harmtotal lossreceipt
Exploitationpublic proof-of-conceptreceipt
Defensefix version namedreceipt
Movementdoubled within 72hreceipt
PLATEAU10Minimal movement since 2026-06-15, 52 days at 0.55, as of 2026-08-06. arc-rules@v1

Foresight · where to check next

SonicWall SMA1000MicrosoftGitLabActiveMQ BrokerCVE-2022-41223langflow-ai44521

This record is one instance of CWE-94, improper control of generation of code ('code injection'). The index holds 7185 prior instances of this class, 79 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

Running Apache Cassandra? 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

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Reachnetwork-reachable · high privileges required · no user interaction · low attack complexityreceipt
ImpactComplete confidentiality, integrity and availability loss, with impact beyond the vulnerable componentreceipt
Scored fromCVSS v3.1 · NVD's vectorreceipt
Weakness classCWE-94 Improper Control of Generation of Code ('Code Injection')receipt
Published consequencesCWE-94: Access Control: Bypass Protection Mechanism; Access Control: Gain Privileges or Assume Identity; Integrity, Confidentiality, Availability: Execute Unauthorized Code or Commands…[email protected]

CISA KEV & Federal Remediation Deadline from the record and CISA

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

Fixed in3.0.26; 3.11.12; 4.0.2receipt
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: Proof-of-concept published · 1 public repository, 2022-02-24.

  • RUNG 1Nothing observed in held sources
  • RUNG 2Proof-of-concept published · 1 public repository2022-02-24receipt
  • RUNG 3Exploited in the wild · CISA KEV listed
  • RUNG 4Ransomware campaign use known

Authority who says so

CVSS, NVD9.1 CRITICALreceipt
Exploit probability0.55006 · top 1% of all CVEsreceipt
Blast breadth1 product across 1 vendorderived
Assigned byapachereceipt
Recorded changes56 · last 18 Sep 2026derived

Affected & Fixed Versions as published

Affected productApache Software Foundation Apache Cassandrareceipt
Published rangesapache cassandra >= 3.0.0 < 3.0.26; apache cassandra >= 3.11.0 < 3.11.12; apache cassandra >= 4.0.0 < 4.0.2receipt
Fixed in3.0.26; 3.11.12; 4.0.2receipt

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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What it is stated by the CNA

When running Apache Cassandra with the following configuration: enable_user_defined_functions: true enable_scripted_user_defined_functions: true enable_user_defined_functions_threads: false it is possible for an attacker to execute arbitrary code on the host. The attacker would need to have enough permissions to create user defined functions in the cluster to be able to exploit this. Note that this configuration is documented as unsafe, and will continue to be considered unsafe after this CVE. receipt

NVD's analysis a second authority

severity
9.1 CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
weakness
CWE-94; CWE-732
affected versions
apache cassandra >= 3.0.0 < 3.0.26; apache cassandra >= 3.11.0 < 3.11.12; apache cassandra >= 4.0.0 < 4.0.2

check it yourself lists.apache.org openwall.com jfrog.com security.netapp.com receipt

Dated events

2022-02-25EPSS moved 0.02 to 0.222025-03-17EPSS moved 0.45 to 0.912026-06-15EPSS moved 0.91 to 0.55

Movement the material steps

13 Feb 20220.02485
25 Feb 20220.21903 · crossed 0.10
4 Mar 20220.42841
7 Mar 20230.00531 · crossed 0.10 · scoring model v2023.03.01
17 Dec 20240.34277 · crossed 0.10
16 Mar 20250.44951
17 Mar 20250.91405 · crossed 0.50 and 0.90 · scoring model v2025.03.14
18 Nov 20250.63904 · crossed 0.90
21 Nov 20250.91824 · crossed 0.90
15 Jun 20260.54889 · crossed 0.90 · scoring model v2026.06.15
6 Aug 20260.55006

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

Show all 51 observations
13 Feb 20220.02485
17 Feb 20220.01549
18 Feb 20220.02199
25 Feb 20220.21903
26 Feb 20220.27305
4 Mar 20220.42841
7 Mar 20230.00531
28 Mar 20230.00851
19 May 20230.00789
28 Jun 20230.01026
12 Jul 20230.01212
25 Jul 20230.01709
22 Aug 20230.01983
4 Sep 20230.01814
19 Sep 20230.02134
3 Oct 20230.03773
1 Nov 20230.03840
1 Dec 20230.04939
15 Dec 20230.04449
25 Feb 20240.04594
5 May 20240.05417
2 Jun 20240.05005
9 Aug 20240.05319
27 Oct 20240.05165
22 Nov 20240.05486
17 Dec 20240.34277
20 Dec 20240.35072
30 Jan 20250.41133
28 Feb 20250.41211
16 Mar 20250.44951
17 Mar 20250.91405
29 Mar 20250.92088
30 Mar 20250.91405
9 May 20250.91865
16 Jul 20250.91234
11 Aug 20250.90664
22 Aug 20250.91234
15 Sep 20250.90822
4 Oct 20250.91236
12 Nov 20250.91563
13 Nov 20250.91824
18 Nov 20250.63904
21 Nov 20250.91824
24 Nov 20250.91526
26 Nov 20250.91824
4 Dec 20250.91526
28 Feb 20260.90614
23 Apr 20260.91007
15 Jun 20260.54889
19 Jul 20260.54727
6 Aug 20260.55006

51 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 0.55006Published2022-02-11Public PoC2022-02-24Index as of2026-08-06

Exploit probability more than doubled between 2025-03-16 and 2025-03-17 (0.44951 → 0.91405) and the record had been public for 4 years, 5 months when this index was last written.

Published 2022-02-11 receipt · Public PoC 2022-02-24 receipt · Index as of 2026-08-06 derived

The pattern, elsewhere

This record is one instance of CWE-94, improper control of generation of code ('code injection'). The index holds 7185 prior instances of this class, 79 KEV-listed. The nearest of its KEV-listed records are drawn beside this. [email protected]

CVE-2026-15410 · SonicWall SMA1000matches 7 of 10KEV listed · 2026receipt
CVE-2023-24955 · Microsoft SharePoint Enterprise Server 2016matches 7 of 10KEV listed · 2023receipt
CVE-2021-22205 · GitLabmatches 7 of 10KEV listed · 2021receipt
CVE-2026-34197 · Apache ActiveMQ Brokermatches 7 of 10KEV listed · 2026receipt
CVE-2022-41223matches 6 of 9KEV listed · 2022receipt
CVE-2025-3248 · langflow-ai langflowmatches 6 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

7185 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.

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