CVE-2021-1789
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A type confusion issue was addressed with improved state handling
rank 76 = 40 + 22 + 0 + 8 + 6
rank@v1 · act now
Someone is already using it
CISA KEV catalog · public proof-of-concept · FIRST EPSS
EPSS 0.14479 · CISA KEV listed · without this subject the record ranks 36
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 54
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 76
How much of the world it touches
NVD CPE configurations
12 products in the CPE ranges · without this subject the record ranks 68
Someone else already set the date
CISA KEV remediation due date
CISA remediation date held · without this subject the record ranks 70
$723,000 = $4.99M incident cost x 1 exposure x 0.14479 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
Foresight · where to check next
This record is one instance of CWE-843, access of resource using incompatible type ('type confusion'). The index holds 923 prior instances of this class, 41 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
Written for the ticket you're about to file.
CISA KEV & Federal Remediation Deadline from the record and CISA
The fix, and how long it's been waiting.
Exploit Status & Known PoCs a ladder, not a score
Current rung: Exploited in the wild · CISA KEV listed, 2022-05-04.
- RUNG 1Nothing observed in held sources
- RUNG 2Proof-of-concept published
- RUNG 3Exploited in the wild · CISA KEV listed2022-05-04receipt
- RUNG 4Ransomware campaign use known
Affected & Fixed Versions as published
Show all 12 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.
What it is stated by the CNA
A type confusion issue was addressed with improved state handling. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, tvOS 14.4, watchOS 7.3, iOS 14.4 and iPadOS 14.4, Safari 14.0.3. Processing maliciously crafted web content may lead to arbitrary code execution. receipt
NVD's analysis a second authority
- severity
- 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- weakness
- CWE-843
- affected versions
- apple ipados < 14.4; apple iphone os < 14.4; apple mac os x >= 10.14 < 10.14.6; and 9 more, listed in full below
- also scored by
- 8.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
check it yourself support.apple.com support.apple.com support.apple.com support.apple.com support.apple.com lists.fedoraproject.org +2 morereceipt
Dated events
Movement the material steps
Show all 39 observations
39 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 pattern, elsewhere
This record is one instance of CWE-843, access of resource using incompatible type ('type confusion'). The index holds 923 prior instances of this class, 41 KEV-listed. The nearest of its KEV-listed records are drawn beside this. [email protected]
"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
923 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
These are index-wide views, not findings about CVE-2021-1789.
What usually comes next
Everything above needs no account. What is below is work: assembling it, scoping it to your estate, watching it, and handing it to someone else.