vciy

CVE-2021-3322

INDEX BUILT · 2026-09-20

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Unexpected Pointer Aliasing in IEEE 802154 Fragment Reassembly in Zephyr

CVE-2021-33224 of 4 sources documented this
18

rank 18 = 0 + 16 + 0 + 2 + 0

rank@v1 · backlog

Someone is already using it

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

EPSS 0.00544  ·  without this subject the record ranks 18

What it costs you if it fires

NVD CVSS base score, then the CNA's own

CVSS 6.5, 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 18

How much of the world it touches

NVD CPE configurations

1 product in the CPE ranges  ·  without this subject the record ranks 16

Someone else already set the date

CISA KEV remediation due date

no CISA due date  ·  without this subject the record ranks 18

Unaudited dollar value2 of 3 inputs carry a receipt
Exposure$16,600over 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

$16,600 = $4.99M incident cost x 0.6121449559255632 exposure x 0.00544 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

0.00544EPSSNOT IN KEVas of 2026-09-20
Severity6.5 MEDIUMreceipt
Harmpartial impactreceipt
Exploitationnone in held sources
Defenseunaffected versions publishedreceipt
Movementrisenreceipt
PLATEAU10Minimal movement since 2021-10-13, 1757 days at 0.01, as of 2026-08-05. 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

Running zephyrproject-rtos zephyr? Check your version

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Harm, if it fires from the vector and the weakness

Written for the ticket you're about to file.

Reachreachable from an adjacent network · no privileges required · no user interaction · low attack complexityreceipt
ImpactComplete availability lossreceipt
Scored fromCVSS v3.1 · the CNA's vectorreceipt
Weakness classCWE-476 NULL Pointer Dereferencereceipt
Published consequencesCWE-476: Availability: DoS: Crash, Exit, or Restart; Integrity, Confidentiality: Execute Unauthorized Code or Commands, Read Memory, Modify Memory[email protected]

CISA KEV & Federal Remediation Deadline from the record and CISA

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

First unaffected version, by branchzephyr 2.5.0receipt
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.

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 CNA6.5 MEDIUMreceipt
CVSS, NVD6.5 MEDIUMreceipt
Exploit probability0.00544 · top 55% of all CVEsreceipt
Blast breadth1 product across 1 vendorderived
Assigned byzephyrreceipt
Recorded changes14 · last 19 Sep 2026derived

Affected & Fixed Versions as published

Affected productzephyrproject-rtos zephyrreceipt
Published rangeszephyrproject zephyr >= 2.4.0 < 2.5.0receipt

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.

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Attack path

Adjacent networkno credentials, no interactionzephyrproject-rtos zephyrCWE-476 NULL pointer dereferenceAvailability lossA:Hexploits CWE-476data compromise

What it is stated by the CNA

Unexpected Pointer Aliasing in IEEE 802154 Fragment Reassembly in Zephyr. Zephyr versions >= >=2.4.0 contain NULL Pointer Dereference (CWE-476). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-p86r-gc4r-4mq3 receipt

NVD's analysis a second authority

severity
6.5 CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
weakness
CWE-476
affected versions
zephyrproject zephyr >= 2.4.0 < 2.5.0
also scored by
[email protected] 6.5 CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

check it yourself github.com receipt

Movement the material steps

13 Oct 20210.00416
7 Mar 20234.4e-4 · scoring model v2023.03.01
17 Mar 20250.00095 · scoring model v2025.03.14
15 Jun 20260.00527 · scoring model v2026.06.15
5 Aug 20260.00544
Show all 14 observations
13 Oct 20210.00416
6 Jan 20220.0184
4 Feb 20220.01404
1 Apr 20220.00885
7 Mar 20234.4e-4
8 Mar 20230.00044
25 Mar 20230.00049
5 May 20230.00051
8 Feb 20240.00058
17 Mar 20250.00095
29 Mar 20250.00136
30 Mar 20250.00095
15 Jun 20260.00527
5 Aug 20260.00544

14 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 0.00544Published2021-10-12Index as of2026-08-05

The record had been public for 4 years, 9 months when this index was last written.

Published 2021-10-12 receipt · Index as of 2026-08-05 derived

Siblings and hubs

Records related to this one

Its defect family

zephyrproject-rtos zephyr

Of the 6 records in this family, this is the only one whose title names unexpected aliasing ieee.

Grouped by shared product and weakness, not by shared vulnerability. Each record's own state is on its own page.

Family membership: held values

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What usually comes next

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