CVE-2026-111115VulnerabilityPublished 28 Oct 2026

Apache Kafka's code-generated readers for flexible protocol versions read a tagged-field count declared by the sender

Source GCVE Database

Authoritative record:CVE-2026-111115· High

Not known to be exploited · fixed in 4.2.2 : patch Apache Kafka soon.

Data as of 28 Oct 2026, 22:12 UTC

Severity

High

Rated High by Threat Radar's AI analysis · CVSS not yet scored by NVD

Patch: Available – fixed in 4.2.2

Exploitation evidence

Disclosed: evidence found.
CVE published 28 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

ghsa-7xcv-9qfj-9q57

What to do

Affected software

Product	Affected	Fixed in
Apache Kafkaorg.apache.kafka:kafka	Affected >=2.4.0 <=4.1.2 >=4.2.0 <=4.2.1 >=4.3.0 <=4.3.1	Fixed in–
MavenApache Software Foundation/org.apache.kafka:kafka`pkg:maven/Apache Software Foundation/org.apache.kafka:kafka`Other threats	Affected >=2.4.0 <=4.1.2 >=4.2.0 <=4.2.1 >=4.3.0 <=4.3.1	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Upgrade Apache Kafka to version 4.2.2, 4.3.2, or 4.4.0, where the vulnerability is fixed by adding bounds checks on the tagged-field count. Until upgrading, reduce the socket.request.max.bytes configuration and restrict network access to broker listeners to reduce exposure, though these measures do not fully eliminate the risk.

Description

Apache Kafka's flexible protocol version readers do not properly limit the count of tagged fields declared by the sender, allowing a client to specify an excessively large number of tagged fields in request headers. This can cause the broker to allocate a large number of objects, exhausting heap memory or causing significant garbage collection delays, resulting in denial of service. The issue affects the parsing of flexible request headers, including pre-authentication APIs, allowing exploitation without authentication. Fixed in Apache Kafka versions 4.2.2, 4.3.2, and 4.4.0 by adding bounds checks on the tagged-field count.

Impact

An unauthenticated client can send a specially crafted request with an excessively large number of tagged fields in the flexible request header, causing the broker to allocate a very large number of RawTaggedField objects. This can exhaust the broker's heap memory or induce process-wide garbage collection stalls, leading to denial of service. The attack can occur before authentication and authorization checks, bypassing resource ACLs and quota enforcement.

References

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