CVE-2021-3864
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A flaw was found in the way the dumpable flag setting was handled when certain SUID binaries executed its descendants
rank 39 = 15 + 18 + 0 + 6 + 0
rank@v1 · scheduled
Someone is already using it
CISA KEV catalog · public proof-of-concept · FIRST EPSS
EPSS 0.00769 · without this subject the record ranks 24
What it costs you if it fires
NVD CVSS base score, then the CNA's own
CVSS 7.0, from NVD · without this subject the record ranks 21
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 39
How much of the world it touches
NVD CPE configurations
5 products in the CPE ranges · without this subject the record ranks 33
Someone else already set the date
CISA KEV remediation due date
no CISA due date · without this subject the record ranks 39
Hindsight · the state
Foresight · where to check next
This record is one instance of CWE-284, improper access control. The index holds 8361 prior instances of this class, 36 KEV-listed. The nearest of its KEV-listed records are drawn beside this. taxonomy@v1
Running kernel? Check your version
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Harm, if it fires from the vector and the weakness
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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: Proof-of-concept published · 1 public repository, 2022-03-31.
- RUNG 1Nothing observed in held sources
- RUNG 2Proof-of-concept published · 1 public repository2022-03-31receipt
- RUNG 3Exploited in the wild · CISA KEV listed
- RUNG 4Ransomware campaign use known
Affected & Fixed Versions as published
Show all 5 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.
$38,400 = $4.99M incident cost x 1 exposure x 0.00769 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 way the dumpable flag setting was handled when certain SUID binaries executed its descendants. The prerequisite is a SUID binary that sets real UID equal to effective UID, and real GID equal to effective GID. The descendant will then have a dumpable value set to 1. As a result, if the descendant process crashes and core_pattern is set to a relative value, its core dump is stored in the current directory with uid:gid permissions. An unprivileged local user with eligible root SUID binary could use this flaw to place core dumps into root-owned directories, potentially resulting in escalation of privileges. receipt
NVD's analysis a second authority
- severity
- 7 CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- weakness
- CWE-284
- affected versions
- debian linux 10.0; debian linux 11.0; redhat enterprise linux 6.0; and 2 more, listed in full below
check it yourself openwall.com bugzilla.redhat.com access.redhat.com lore.kernel.org lore.kernel.org lore.kernel.org +1 morereceipt
Movement the material steps
Show all 71 observations
71 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-284, improper access control. The index holds 8361 prior instances of this class, 36 KEV-listed. The nearest of its KEV-listed records are drawn beside this. cwe-consequences@4.20
"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
8361 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
None. No alias set, and nothing in the corpus cites this identifier or shares its product family within 60 days.
Browse the index from here
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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.