vciy

CVE-2021-26828

INDEX BUILT · 2026-09-20

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Print this page to keep the view as it stands on this date. Everything hidden behind a disclosure opens, and every receipt prints with its value.

OpenPLC ScadaBR through 0.9.1 on Linux and through 1.12.4 on Windows allows remote authenticated users to upload and execute arbitrary JSP files via…

CVE-2021-268283 of 4 sources documented this
79

rank 79 = 40 + 22 + 5 + 4 + 8

rank@v1 · act now

Someone is already using it

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

EPSS 0.39356 · CISA KEV listed  ·  without this subject the record ranks 39

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 57

It is getting worse, not staying still

FIRST EPSS series, rescorings and bad loads removed

rose on 2025-12-04  ·  without this subject the record ranks 74

How much of the world it touches

NVD CPE configurations

2 products in the CPE ranges  ·  without this subject the record ranks 75

Someone else already set the date

CISA KEV remediation due date

CISA remediation date held  ·  without this subject the record ranks 71

Unaudited dollar value2 of 3 inputs carry a receipt
Exposure$1.96Mover the next 30 days, if this record is yours
Movement+$1.61Mon 2025-11-21, the last material move, 9 months before this reading
Basisassumeda published average, not your estate

$1.96M = $4.99M incident cost x 1 exposure x 0.39356 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

0.39356EPSSKEV · LISTED
Severity8.8 HIGHreceipt
Harmtotal lossreceipt
Exploitationin the wild · KEVreceipt
Defenseno fix version held
Movementdoubled within 72hreceipt
PLATEAU10Minimal movement since 2026-06-15, 81 days at 0.39, as of 2026-09-04. arc-rules@v1

Foresight · where to check next

SamsungTrend Micro ApexDrupal CoreSierra WirelessCVE-2024-50623SonicWall Email26828

This record is one instance of CWE-434, unrestricted upload of file with dangerous type. The index holds 4431 prior instances of this class, 26 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

Check a version against this record

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Harm, if it fires from the vector and the weakness

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Reachnetwork-reachable · low privileges required · no user interaction · low attack complexityreceipt
ImpactComplete confidentiality, integrity and availability lossreceipt
Scored fromCVSS v3.1 · NVD's vectorreceipt
Weakness classCWE-434 Unrestricted Upload of File with Dangerous Typereceipt
Published consequencesCWE-434: Integrity, Confidentiality, Availability: Execute Unauthorized Code or Commands[email protected]
Ransomware campaign useUnknown to CISAreceipt

CISA KEV & Federal Remediation Deadline from the record and CISA

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

Fixed inNo fix version in held sources, as the index stood on 4 Sep 2026.
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.
CISA remediation statusoverdue since 2025-12-24receipt
CISA required actionApply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.receipt
Published to CISA KEV1636 daysderived

Exploit Status & Known PoCs a ladder, not a score

Current rung: Exploited in the wild · CISA KEV listed, 2025-12-03.

  • RUNG 1Nothing observed in held sources
  • RUNG 2Proof-of-concept published · 2 public repositories2021-03-31receipt
  • RUNG 3Exploited in the wild · CISA KEV listed2025-12-03receipt
  • RUNG 4Ransomware campaign use known

Authority who says so

CVSS, NVD8.8 HIGHreceipt
Exploit probability0.39356 · top 1% of all CVEsreceipt
Blast breadth1 product across 1 vendorderived
Assigned bymitrereceipt
Recorded changes57 · last 19 Sep 2026derived

Affected & Fixed Versions as published

Named in the CPE rangesScadabrreceipt
Published rangesscadabr <= 0.9.1; scadabr <= 1.12.4receipt

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

OpenPLC ScadaBR through 0.9.1 on Linux and through 1.12.4 on Windows allows remote authenticated users to upload and execute arbitrary JSP files via view_edit.shtm. receipt

NVD's analysis a second authority

severity
8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
weakness
CWE-434
affected versions
scadabr <= 0.9.1; scadabr <= 1.12.4
also scored by
8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

check it yourself youtu.be packetstormsecurity.com forum.scadabr.com.br receipt

Dated events

2022-02-04EPSS moved 0.05 to 0.122025-03-17EPSS moved 0.02 to 0.522025-12-03Added to CISA KEV2025-12-24CISA remediation due2026-06-15EPSS moved 0.83 to 0.39

Movement the material steps

12 Jun 20210.04526
4 Feb 20220.11752 · crossed 0.10
7 Mar 20230.00731 · crossed 0.10 · scoring model v2023.03.01
17 Mar 20250.5197 · crossed 0.10 and 0.50 · scoring model v2025.03.14
20 Apr 20250.456 · crossed 0.50
10 May 20250.5053 · crossed 0.50
18 Nov 20250.20322 · crossed 0.50
21 Nov 20250.52654 · crossed 0.50
4 Dec 20250.84324
15 Jun 20260.39356 · crossed 0.50 · scoring model v2026.06.15
19 Jul 20260.39356

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

Show all 43 observations
12 Jun 20210.04526
4 Feb 20220.11752
7 Mar 20230.00731
3 Sep 20230.00875
14 Jun 20240.01237
14 Jul 20240.01273
14 Oct 20240.01283
17 Dec 20240.01504
23 Jan 20250.01831
26 Feb 20250.02175
17 Mar 20250.5197
19 Mar 20250.61828
20 Mar 20250.5197
27 Mar 20250.61828
28 Mar 20250.5197
29 Mar 20250.61828
30 Mar 20250.5197
20 Apr 20250.456
10 May 20250.5053
4 Jun 20250.56853
15 Jun 20250.5053
17 Oct 20250.5314
26 Oct 20250.52654
18 Nov 20250.20322
21 Nov 20250.52654
4 Dec 20250.84324
5 Dec 20250.8012
6 Dec 20250.8236
7 Dec 20250.8012
10 Dec 20250.81551
11 Dec 20250.8012
18 Dec 20250.81551
19 Dec 20250.8012
21 Jan 20260.78546
14 Feb 20260.80017
18 Feb 20260.80023
19 Feb 20260.80017
27 May 20260.78433
11 Jun 20260.80017
13 Jun 20260.82764
15 Jun 20260.39356
27 Jun 20260.39096
19 Jul 20260.39356

43 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 0.39356Public PoC2021-03-31Published2021-06-11CISA KEV2025-12-03Index as of2026-09-04

Listed by CISA 1636 days after it published, exploit probability more than doubled between 2025-11-18 and 2025-11-21 (0.20322 → 0.52654) and the record had been public for 5 years, 2 months when this index was last written.

No material movement in 47 days as of the last ingest this index recorded.

Public PoC 2021-03-31 receipt · Published 2021-06-11 receipt · CISA KEV 2025-12-03 receipt · Index as of 2026-09-04 derived

The pattern, elsewhere

This record is one instance of CWE-434, unrestricted upload of file with dangerous type. The index holds 4431 prior instances of this class, 26 KEV-listed. The nearest of its KEV-listed records are drawn beside this. [email protected]

CVE-2024-7399 · Samsung Electronics MagicINFO 9 Servermatches 8 of 8KEV listed · 2024receipt
CVE-2021-36741 · Trend Micro Apex Onematches 8 of 8KEV listed · 2021receipt
CVE-2020-13671 · Drupal Corematches 8 of 8KEV listed · 2020receipt
CVE-2018-4063 · Sierra Wirelessmatches 8 of 8KEV listed · 2019receipt
CVE-2024-50623matches 7 of 8KEV listed · 2024receipt
CVE-2021-20022 · SonicWall Email Securitymatches 7 of 8KEV listed · 2021receipt

"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

4431 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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