CVE-2023-34040
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Java Deserialization vulnerability in Spring-Kafka When Improperly Configured
rank 40 = 15 + 20 + 1 + 4 + 0
rank@v1 · scheduled
Someone is already using it
CISA KEV catalog · public proof-of-concept · FIRST EPSS
EPSS 0.02090 · without this subject the record ranks 25
What it costs you if it fires
NVD CVSS base score, then the CNA's own
CVSS 7.8, from NVD · without this subject the record ranks 20
It is getting worse, not staying still
FIRST EPSS series, rescorings and bad loads removed
rose on 2025-09-11 · without this subject the record ranks 39
How much of the world it touches
NVD CPE configurations
2 products in the CPE ranges · without this subject the record ranks 36
Someone else already set the date
CISA KEV remediation due date
no CISA due date · without this subject the record ranks 40
Hindsight · the state
Foresight · where to check next
This record is one instance of CWE-502, deserialization of untrusted data. The index holds 3513 prior instances of this class, 76 KEV-listed. The nearest of its KEV-listed records are drawn beside this. taxonomy@v1
Sources disagree here.
Both shown, dated. We don't pick winners. disagreement-rules@v1
Running Spring For Apache Kafka? 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 · 4 public repositories, 2023-08-30.
- RUNG 1Nothing observed in held sources
- RUNG 2Proof-of-concept published · 4 public repositories2023-08-30receipt
- RUNG 3Exploited in the wild · CISA KEV listed
- RUNG 4Ransomware campaign use known
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.
$59,900 = $4.99M incident cost x 0.5743756121449558 exposure x 0.0209 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
In Spring for Apache Kafka 3.0.9 and earlier and versions 2.9.10 and earlier, a possible deserialization attack vector existed, but only if unusual configuration was applied. An attacker would have to construct a malicious serialized object in one of the deserialization exception record headers. Specifically, an application is vulnerable when all of the following are true: * The user does not configure an ErrorHandlingDeserializer for the key and/or value of the record * The user explicitly sets container properties checkDeserExWhenKeyNull and/or checkDeserExWhenValueNull container properties to true. * The user allows untrusted sources to publish to a Kafka topic By default, t receipt
Read the rest of the CNA's description
hese properties are false, and the container only attempts to deserialize the headers if an ErrorHandlingDeserializer is configured. The ErrorHandlingDeserializer prevents the vulnerability by removing any such malicious headers before processing the record.
NVD's analysis a second authority
- severity
- 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- weakness
- CWE-502
- affected versions
- vmware spring for apache kafka >= 2.8.1 <= 2.9.10; vmware spring for apache kafka >= 3.0.0 <= 3.0.9
- also scored by
- security@vmware.com 5.3 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
The CNA scored it 5.3 and NVD 7.8. Both are shown because both were published; we do not pick one.
Dated events
Movement the material steps
This score more than doubled inside 72 hours. Both observations are in the full history below.
Show all 21 observations
21 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-502, deserialization of untrusted data. The index holds 3513 prior instances of this class, 76 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
3513 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. Its defect family is below.
Its defect family
spring for apache kafka
Of the 2 records in this family, this is the only one holding a stated fix version: 2.9.11; 3.0.10.
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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