CVE-2021-3772
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A flaw was found in the Linux SCTP stack
rank 27 = 0 + 16 + 0 + 11 + 0
rank@v1 · scheduled
Someone is already using it
CISA KEV catalog · public proof-of-concept · FIRST EPSS
EPSS 0.01240 · without this subject the record ranks 27
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 11
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
25 products 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 27
Hindsight · the state
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.
Running kernel? 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.
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 25 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.
$44,400 = $4.99M incident cost x 0.7179585840212677 exposure x 0.0124 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.
What it is stated by the CNA
A flaw was found in the Linux SCTP stack. A blind attacker may be able to kill an existing SCTP association through invalid chunks if the attacker knows the IP-addresses and port numbers being used and the attacker can send packets with spoofed IP addresses. receipt
NVD's analysis a second authority
- severity
- 6.5 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H
- weakness
- CWE-354
- affected versions
- linux kernel < 5.15.0; redhat enterprise linux 8.0; debian linux 9.0; and 22 more, listed in full below
check it yourself bugzilla.redhat.com ubuntu.com git.kernel.org github.com lists.debian.org debian.org +2 morereceipt
Movement the material steps
Show all 50 observations
50 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
The record had been public for 4 years, 4 months when this index was last written.
Siblings and hubs
Records related to this one
No record cites this identifier and it carries no alias. Its defect family is below.
Its defect family
kernel
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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Browse the index from here
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What usually comes next
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